3D printer systems and methods

ABSTRACT

A print head comprising two shafts disposed in opposite sides of a filament to drive the filament to a heated chamber for delivering a molten material. The shafts are actively driven, for example, by two independent motors. The two shaft configuration of the print head can improve a control of the filament movement rate, especially for soft filament materials.

The present application claims priority from U.S. Provisional PatentApplication Ser. No. 62/310,816, filed on Mar. 21, 2016 entitled: “3Dprinter systems and methods” (HYREL009-PRO), which is incorporatedherein by reference.

BACKGROUND OF THE INVENTION

3D printers can be used to build solid objects by printing layers bylayers of building materials. The building materials can be in liquid orsemi liquid form at the 3D printer head, for example, a solid materialcan be heated and then extruded from a 3D printer nozzle. The layers ofbuilding materials can be solidified on a substrate.

3D printer systems can use a fused filament fabrication (FFF) process(sometimes called fused deposition modeling (FDM) process) in which afilament is moved, e.g., by a filament moving mechanism, toward a heatedzone. The filament can be melted, and extruded on a platform to form a3D object. The melted filament can adhere to the walls of the heatedprinter head, resulting in a deformed printed lines.

It would therefore be advantageous to have advanced 3D printing systemsand methods that have improved printing mechanisms.

SUMMARY OF THE DESCRIPTION

In some embodiments, the present invention discloses a print head for a3D printer for printing a structure using a filament. The print head caninclude two hobbed shafts disposed in opposite sides of the filament andcontacting the filament. The shafts can be configured to rotate inopposite directions for driving the filament, for example to a heatedchamber. The heated chamber can be configured to heat the filament to amelting temperature, so that the print head can deliver a moltenmaterial.

In some embodiments, one shaft of the two shafts can be coupled to amotor, e.g., to be actively driven by the motor. The other shaft can becoupled to the one shaft by a coupling mechanism, such as by a gear setor by a belt.

In some embodiments, each shaft can be coupled to one motor, e.g., twoshafts can be coupled to two independent motors. The motors can beindependent, e.g., the filament can be actively driven by the twoindependent motors. The motors can be driven at a same speed or atdifferent speeds, for example, to ensure an appropriate delivering ofmaterial to the heated chamber.

In some embodiments, an assembly, such as a spring assembly, can becoupled to the print head to adjust the distance between the two shafts.The adjustment can be used to change a friction with the filament, e.g.,a driving force to the filament. For example, a soft filament might needa smaller distance to ensure an appropriate force to the filament todrive the filament.

The print head can be coupled to a 3D printer, such as movably coupled,e.g., the print head can be securely coupled to the 3D printer and canbe removed from the 3D printer.

In some embodiments, the print head can include a conduit having achannel for guiding the filament. The diameter of the channel can beabout the size of the filament, so that the filament can easily movewithin the channel. Further, the conduit can include a low frictionmaterial, such as Teflon, which can assist in the movements of thefilament.

The print head can include two motors with each motor having a shaft.The motors are configured to drive the filament along the channel bycontact, e.g., the motor shafts can be in contact with the filament, sothat the motors turn, the friction with the filament can drive thefilament. The contact can be a direct contact, e.g., the motor shaftscan directly contact the filament. To increase a friction force, aportion of the surface of the shafts can be hobbed, e.g., roughened. Thehobbed surfaces can then contact the filament for driving the filament.

The contact can be an indirect contact, e.g., the motor shafts cancontact the filament through an element fixedly coupled to the shafts.For example, a gear or a disc with an irregular circumference surfacecan be coupled to a shaft. The teeth of the gear of the irregularsurface can increase a friction while in contact with the filament. Thehigh friction can assist in moving the filament along the guidingchannel.

In some embodiments, the conduit can include two cut portions foraccepting the two shafts or the gears (e.g., a gear or a disc) fixedlycoupled to the shafts. The cut portions can be at two opposite side ofthe conduit, cut through the conduit until reaching the channel. Eachcut portion can expose a portion of the channel. A shaft can passthrough the cut portion, with a portion of the shaft surface, e.g., thehobbed surface, contacting the filament through the corresponded exposedportion. Alternatively, a shaft can pass through the cut portion, with agear surface contacting the filament through the corresponded exposedportion. With the conduit having the cut portions, the filament isconstrained in the intended path, e.g., along the channel direction. Theconduit can ease the insertion of the filament to the print head, sincethe filament just need to enter the conduit. Subsequent movements of thefilament can be guided by the conduit. The conduit can also prevent theaccumulation of filament in the area under the shafts, especially if thedownstream of the filament path is blocked. Essentially, the conduitalmost completely covers the filament, e.g., the cut portions can exposesections of the filament, but the exposed sections are blocked by theshafts or the gears.

In some embodiments, the shafts can be disposed in parallel with eachother and perpendicular to the conduit. The shafts can be configured tobe in opposite sides of the filament and contacting the filament. Themotors can be disposed in opposite directions with respect to theconduit. The shafts can be configured to rotate in opposite directionsfor driving the filament along the channel.

In some embodiments, an assembly can be coupled to one shaft or onemotor or one motor mount, for example, for pushing the one shaft to theother shaft, e.g. for adjusting a distance between the two shafts. Theassembly can be spring loaded.

In some embodiments, the motors can be coupled to separate motor mounts.The separate motor mounts can be coupled to each other so that one motormount of the two motor mounts is configured to move with respect to theother motor mount. The movement can be linear movements, e.g., one motormount can be linearly translated with respect to the other motor mount,to adjust a distance between the two motor shafts. The movement can berotation movements, e.g., one motor mount can be rotated with respect tothe other motor mount, to adjust a distance between the two motorshafts.

In some embodiments, the print head can be coupled to a 3D printer, suchas removably coupled. For example, the print head can be coupled to the3D printer for printing a soft material. The print head can then beremoved from the 3D printer, and another print head can be installed forprinting a different material.

In some embodiments, an acoustic sensor can be included for detecting acondition of the two motors. The acoustic sensor can be coupled to theprint head or to the 3D printer. The acoustic sensor can detect a normalsound, e.g., the amplitude and the frequency of the sound, of the motorswhen running, and can report that things are running properly. Theacoustic sensor can detect an abnormal sound, e.g., from a change in theamplitude and/or the frequency of the sound, of the motors when running,and can report that there seems to be a problem. A controller can decideto stop the printing process, or can automatically adjust an operatingcondition of the motors, such as changing a speed or changing anacceleration of the motors.

In some embodiments, an acoustic sensor can be included for detecting acontact of the print head with an object. The acoustic sensor can becoupled to the print head or to the 3D printer. For example, the printhead can move downward to contact a platform of the 3D printer. Beforethe contact, the acoustic sensor can detect a normal sound of themotors. After the contact, the sound can change, e.g., changing in theamplitude and/or the frequency of the sound. A controller can determinethe location that the print head contact the platform, and can set thelocation to be a reference point for the platform with respect to theprint head.

In some embodiments, an acoustic sensor can be included for leveling aplatform of a 3D printer. The acoustic sensor can be coupled to theprint head or to the 3D printer. For example, the print head can move toa first point, and then find a first contacting location of the printhead with the platform. The print head can move to another point, andcan repeat the process to find a second contacting location. With threecontacting locations, the 3D printer can level the platform. Forexample, the platform can be adjusted so that the contacting locationsare located in a plane perpendicular to the print head. Alternatively, asoftware correction algorithm can be used so that the print head canprint on a non-perpendicular plane (if the contacting locations are on aplane) or on an irregular surface (if the contacting locations do notform a planar surface).

In some embodiments, the present invention discloses a method to use theprint head with two independent motors driving a filament. The methodcan include activating the two motors to rotate in opposite direction,wherein each motor comprises a shaft, wherein the two shafts areconfigured to drive a filament along a channel of a conduit to a heatedchamber for delivering a molten material. The method can also includemoving the motors to print an object with the molten material.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a prior art 3D print head according to someembodiments.

FIG. 2A-2E illustrate a configuration for a filament delivery assemblyaccording to some embodiments.

FIGS. 3A-3C illustrate flow charts for filament delivering according tosome embodiments.

FIG. 4A-4E illustrate a configuration for a filament delivery assemblyaccording to some embodiments.

FIG. 5A-5E illustrate a configuration for a filament delivery assemblyaccording to some embodiments.

FIG. 6 illustrates a flow chart for filament delivering according tosome embodiments.

FIG. 7A-7D illustrate a configuration for a filament delivery assemblyaccording to some embodiments.

FIGS. 8A-8B illustrate flow charts for filament delivering according tosome embodiments.

FIG. 9A-9D illustrate a configuration for a filament delivery assemblyaccording to some embodiments.

FIGS. 10A-10C illustrate configurations for a filament delivery assemblyaccording to some embodiments.

FIGS. 11A-11B illustrate flow charts for filament delivering accordingto some embodiments.

FIGS. 12A-12C illustrate acoustic sensor configurations according tosome embodiments.

FIGS. 13A-13C illustrate flow charts for acoustic signal configurationsaccording to some embodiments.

FIGS. 14A-14D illustrate contact sensing configurations using anacoustic sensor assembly according to some embodiments.

FIGS. 15A-15C illustrate contact sensing configurations using anacoustic sensor assembly according to some embodiments.

FIGS. 16A-16C illustrate a leveling configuration using an acousticsensor assembly according to some embodiments.

FIG. 17 illustrates a 3D printer configuration according to someembodiments.

FIGS. 18A-18D illustrate configurations for 3D printers according tosome embodiments.

FIGS. 19A-19B illustrate a flexible layer having carbon fiber meshaccording to some embodiments.

FIGS. 20A-20B illustrate configurations for carbon fiber mesh reinforcedflexible layers according to some embodiments.

FIGS. 21A-21C illustrate configurations for flexible layers with supportstructures according to some embodiments.

FIGS. 22A-22B illustrate flow charts for reinforcing flexible layerswith carbon fiber mesh according to some embodiments.

FIGS. 23A-23E illustrate a process for forming a carbon fiber meshreinforce flexible layer according to some embodiments.

FIGS. 24A-24E illustrate a process for forming a carbon fiber meshreinforce flexible layer according to some embodiments.

FIGS. 25A-25D illustrate configurations of carbon fiber mesh reinforcedflexible layers according to some embodiments.

FIG. 26 illustrates a flow chart for forming carbon fiber meshreinforced flexible layers according to some embodiments.

FIGS. 27A-27C illustrate processes for forming carbon fiber meshreinforced flexible layers according to some embodiments.

FIG. 28 illustrates a flow chart for forming carbon fiber meshreinforced flexible layers according to some embodiments.

FIGS. 29A-29B illustrate processes for forming joints having a carbonfiber mesh reinforced flexible layer according to some embodiments.

FIG. 30 illustrates a flow chart for forming carbon fiber meshreinforced flexible layers according to some embodiments.

FIGS. 31A-31B illustrate processes for forming surface conditioning 3Dprinted objects according to some embodiments.

FIGS. 32A-32B illustrate flow charts for forming surface conditioningobjects for casting according to some embodiments.

FIGS. 33A-33E illustrate configurations of a molding system according tosome embodiments.

FIGS. 34A-34C illustrate different print heads according to someembodiments.

FIGS. 35A-35I illustrate different conditioning heads according to someembodiments.

FIGS. 36A-36B illustrate flow charts for casting objects using surfaceconditioning printed objects according to some embodiments.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Additive manufacturing processes generally fabricate 3D objects bydepositing layers by layers in patterns corresponding to the shape ofthe objects. At each layer, a print head can deposit building materialsat locations corresponded to the pattern of the object for that layer.

3D printing processes can include inkjet printing, stereolithography andfused filament fabrication. In inkjet printing processes, liquidmaterial are released from an inkjet print head, and solidified on thesubstrate surface, e.g., on the model being formed. In stereolithographyprocesses, a UV light can crosslink layers of photopolymer. In fusedfilament fabrication processes, a continuous filament of thermoplasticcan be softened or melted and then re-solidified on a previouslydeposited layer. Alternatively, paste-like materials can be used forprinting, for example, through a pressure extrusion device such as apiton/cylinder.

Various polymers are used, including acrylonitrile butadiene styrene(ABS), polycarbonate (PC), polylactic acid (PLA), high densitypolyethylene (HDPE), PC/ABS, and polyphenylsulfone (PPSU). Othermaterials can be used, such as clay or ceramic materials.

FIG. 1 illustrates a prior art 3D print head according to someembodiments. The print head 100 can be used in a 3D printer system,which can print objects on a platform. The platform can include aheater, which can heat the platform surface. The print head can be movedrelative to the platform, in horizontal and vertical directions, forexample, by computer controlled mechanisms using stepper or servomotors. For example, the printer head can move in a horizontaldirection, such as x. The platform can move in a horizontal directionsuch as y, together with a vertical direction such as z. Other movementconfigurations can be used to provide complete 3D movements of theprinter head relative to the platform.

The print head 100 can accept a filament 110, such as a thermoplasticfilament. The print head 100 can include a delivery mechanism toregulate the flow of the filament 110. For example, a motor rotating agear 120 can be used to push the filament into a heated chamber 150 at acontrolled rate. There can be bearing 130, disposed on an opposite sideof the rotating gear 120 for supporting the filament against therotating gear 120.

The heated chamber 150 can include a heater 152, which can heat thefilament 110 to a temperature that can melt or soften the filamentmaterial, for example, to a temperature higher than the glass transitiontemperature of the filament material. A temperature sensor 154 can beused to regulate the temperature of the heated chamber 150. A nozzle 160can be used to control the size of the molten filament, outputted fromthe print head.

The print head can be thermally isolated from the delivery assembly, forexample, by a low thermal conductivity material. For example, a thermalisolation element 140 can be disposed between the heated chamber 150 andthe rotating gear 120, for example, to prevent heating other componentsof the print head. The thermal isolation element 140 can also befunction as a guide, which can serve for guiding the filament 110, fromthe rotating gear 120 to the heated chamber 150.

There can be a gap 170 between the rotating gear 120 and the guidingelement 140. The filament can escape through the gap 170, for example,if there is a blockage at the guiding element 140 or at the heatedchamber 150.

In addition, the there might not be enough force for the rotating gear120 to push the filament 110. Since there can be only one rotating gear120 pushing the filament against the rotating bearing 130, if there is ablockage, the rotating gear 120 can be slipped. Further, if the filamentincludes a soft material, such as an elastic material or a deformablematerial, the single rotating gear 120 might deform the filament withoutactually moving it toward the guiding element 140.

In some embodiments, the present invention discloses a novel filamentdelivery assembly to deliver a filament. The filament delivery assemblycan be used in a print head of a 3D printer system. The novel filamentdelivery assembly can include a filament guiding assembly and a filamentdriving assembly, which can include an active drive element, such as amotor rotating a hobbed shaft, for driving a filament in the filamentguiding assembly toward a heated chamber.

In some embodiments, the present invention discloses a print head foruse, for example, in a 3D printer system. The print head can include anovel filament delivery assembly.

The filament delivery assembly can include a hollow conduit, which canenclose a filament therein for guiding the filament. The hollow conduitcan include an opening at an end, which can operate as an input foraccepting the filament. The other end of the hollow conduit can becoupled to the heated chamber, e.g., for guiding the filament along thehollow conduit toward the heated chamber. The hollow conduit can beextended from the heated chamber to pass a filament driving assembly,such as a hobbed shaft of a motor or a tooth gear coupled to a shaft ofa motor. The filament driving assembly can be located between the inputof the hollow conduit and the heated chamber.

The hollow conduit can be configured for supporting the filament againstthe filament driving assembly, e.g., against the hobbed shaft or a gearshaft of a motor. The hollow conduit can eliminate spaces after thefilament driving assembly, e.g., between the filament driving assemblyand the heated chamber, thus can reduce potential filament mis-guidingproblems. In addition, the hollow conduit can simplify the print headconstruction, for example, by eliminating the bearing assembly that isused as a support the filament driving assembly.

FIG. 2A-2E illustrate a configuration for a filament delivery assemblyaccording to some embodiments. A filament delivery assembly 200 can beused in a print head, which can include coupling elements for couplingto movement assemblies, e.g., for moving in x, y, or z directions, of a3D printer system. The print head can include a heated chamber 250,which can accept a filament input from the filament delivery assembly,and deliver molten filament to a nozzle 260 for printing on a platform.The heated chamber 250 can include a heater 252 and a temperature sensor254, for regulating a temperature of the heated chamber.

A filament delivery assembly 200 can include a filament driving assembly220, which can include a motor 222 driving a hobbled shaft or a gearshaft. For example, FIG. 2D shows a motor 270 having a shaft 271 coupledwith a gear 272. The uneven surface of the gear can touch the filament,and when the shaft is rotated, the gear is also rotated, and the unevensurface of the gear can move the filament. FIG. 2E shows a motor 275having a shaft 276 hobbed 272 277, e.g., forming a rough or unevensurface or teeth on a surface of the shaft. For example, the hobbingaction can form marking on the shaft, which can generate a roughsurface. The rough surface of the hobbed portion of the shaft can touchthe filament, and when the shaft is rotated, the rough surface of theshaft can catch the filament to move the filament.

A filament delivery assembly 200 can be include a filament guidingassembly, which can include a hollow conduit 240. The hollow conduit caninclude a material with low friction, such as Teflon. The hollow conduitcan include a material with low thermal conductivity for thermalisolation, e.g., reducing the amount of heat that can reach the filamentdriving assembly from the heated chamber.

The hollow conduit 240 can include an input opening at one end foraccepting a filament 210. The hollow conduit 240 can include an openingat an opposite end for coupling with the heated chamber, e.g., to guidethe filament toward the heated chamber. The hollow conduit 240 caninclude a cut portion 225, which can allow the motor shaft 220 to passthrough for contacting the filament. When the motor rotates, thefilament can be pulled into the hollow conduit from the input opening.The motor can also push the filament, along the hollow conduit, towardthe heated chamber.

The hollow conduit can cover, e.g., guide, the filament before thefilament reaches the filament driving assembly 220, such as the rotatinggear or hobbed portion of the motor shaft. The filament can be guidedafter the pushing action of the filament driving assembly, thus thefilament delivery assembly can prevent or eliminate spilling of thefilament, such as preventing the filament from being driven to anotherlocation when the heated chamber is blocked.

In some embodiments, the hollow conduit can include holes 245, forexample, to increase a thermal isolation from the heated chamber to themotor shaft. A fan can be included, for blowing passing the holes andthe hollow conduit, further reducing a temperature at the motor shaft.

In some embodiments, a force can be applied to push the hollow conduit240 relative to the motor shaft 220. The force can be used to increase afriction between the motor shaft and the filament, which can preventslippage of the filament. As shown, a force 233 can be used to push thehollow conduit against the motor shaft. Alternatively, a force can beapplied to the motor to push the motor shaft against the hollow conduit.

FIGS. 3A-3C illustrate flow charts for filament delivering according tosome embodiments. In FIG. 3A, operation 300 guides a filament between afilament driving assembly and a filament heating assembly. The filamentcan also be guided before and/or during the filament driving assembly.The complete filament guidance can prevent mis-directing of thefilament, for example, in unexpected events such as a blockage in thefilament heating assembly.

In FIG. 3B, operation 320 provides a hollow conduit for accepting afilament. Operation 340 330 forms a cut in the conduit for passing afilament driving assembly, wherein the filament driving assembly iscoupled to the filament for driving the filament along the conduit. Thecut can be formed by drilling a hole through the hollow conduit. Thehole can be configured to expose a portion of the filament to an outsideambient, e.g., the hole diameter can be larger than a thickness of thehollow conduit, and after formed, the hole can expose the hollow portionof the hollow conduit to the outside ambient. The hole diameter can beslightly larger than a diameter of the hobbed portion of a motor shaft,or slightly larger than a diameter of a gear coupled to a motor shaft.

In some embodiments, holes can be formed on the hollow conduit. A springassembly can be incorporated for pushing the hollow conduit against thefilament driving assembly. Support elements can be added around thehollow conduit, for example, for supporting the hollow conduit and/orsupporting the filament driving assembly, such as a motor.

In FIG. 3C, operation 350 uses a hollow conduit to guide a filament witha filament driving assembly driving the filament along the conduit. Thefilament driving assembly can include a motor having a motor shaft. Agear can be fixed coupled to the motor shaft. Alternatively, the motorshaft can be hobbed for forming rough surface on a portion of the motorshaft. The rough surface can contact the filament, and can move thefilament along the hollow portion of the hollow conduit.

In some embodiments, the present invention discloses a novel filamentdelivery assembly to deliver a filament, together with a print headincorporating the filament delivery assembly. The filament deliveryassembly can include a filament driving assembly, which can include anactive drive element, such as a motor rotating a hobbed shaft, and afollower element, such as a rotatable bearing that can be pressedagainst the active drive element.

The filament delivery assembly can include a hollow conduit, which canenclose a filament therein for guiding the filament. The hollow conduitcan be extended from the heated chamber to pass a filament drivingassembly, such as a hobbed shaft of a motor or a tooth gear coupled to ashaft of a motor. The filament driving assembly can be located betweenthe input of the hollow conduit and the heated chamber. The hollowconduit can eliminate spaces after the filament driving assembly, e.g.,between the filament driving assembly and the heated chamber, thus canreduce potential filament mis-guiding problems.

The filament delivery assembly can include a rotatable element, such asa bearing, which can assist in pushing the filament toward active driveelement, such as a hobbed portion of a motor shaft. The bearing can alsobe hobbed, for example, to reduce slippage to the filament.

FIG. 4A-4E illustrate a configuration for a filament delivery assemblyaccording to some embodiments. A filament delivery assembly 400 can beused in a print head, which can include coupling elements for couplingto movement assemblies, e.g., for moving in x, y, or z directions, of a4D printer system. The print head can include a heated chamber 450,which can accept a filament 410 input from the filament deliveryassembly, and deliver molten filament to a nozzle 460 for printing on aplatform. The heated chamber 450 can include a heater 452 and atemperature sensor 454, for regulating a temperature of the heatedchamber.

A filament delivery assembly 400 can include a filament driving assembly420, which can include an active drive element such as a motor 422driving a hobbled shaft or a gear shaft. The filament driving assemblycan include a follower element, such as a rotatable element such as abearing 430. The active drive element and the follower element can bepushed against the filament, such as pushing in opposite directions. Theactive drive element can drive the filament along a filament guidingassembly, and the follower element can assist in maintaining appropriatefriction between the active element and the filament.

A filament delivery assembly 400 can be include a filament guidingassembly, which can include a hollow conduit 440. The hollow conduit caninclude a material with low friction, such as Teflon. The hollow conduitcan include a material with low thermal conductivity for thermalisolation, e.g., reducing the amount of heat that can reach the filamentdriving assembly from the heated chamber.

The hollow conduit 440 can include a cut portion 425, which can allowthe motor shaft 420 to pass through for contacting the filament. Thehollow conduit 440 can include another cut portion 435, which can allowthe rotatable bearing 430 having a bearing shaft 437 to pass through forcontacting the filament. The cut portions 425 and 435 can be slightlylarger than a diameter of the hobbed motor shaft 420 and the bearing430, respectively, for allowing the motor shaft and the bearing to drivethe filament along the hollow conduit. The cut portions can cut throughthe hollow conduit, e.g., by a drill bit.

When the motor rotates, the filament can be pulled into the hollowconduit from the input opening. The movement of the filament can rotatethe rotatable bearing. The motor can also push the filament, along thehollow conduit, toward the heated chamber.

In some embodiments, the hollow conduit can include holes, for example,to increase a thermal isolation from the heated chamber to the motorshaft. A fan can be included, for blowing passing the holes and thehollow conduit, further reducing a temperature at the motor shaft.

In some embodiments, a force can be applied to push the followerelement, e.g., the rotatable bearing 430 relative to the motor shaft420. The force can be used to increase a friction between the motorshaft and the filament, which can prevent slippage of the filament. Asshown, a force 433 can be used to push the rotatable bearing against themotor shaft. Alternatively, a force can be applied to the motor to pushthe motor shaft against the rotatable bearing.

FIG. 5A-5E illustrate a configuration for a filament delivery assemblyaccording to some embodiments. A filament delivery assembly 500 can beused in a print head, including a heated chamber 550.

A filament delivery assembly 500 can include a filament driving assembly520, which can include an active drive element such as a motor 522driving a hobbled shaft or a gear shaft. The filament driving assemblycan include a follower element, such as a rotatable element such as abearing 530.

A filament delivery assembly 500 can be include a filament guidingassembly, which can include a hollow conduit 540. The hollow conduit 540can include a cut portion 525, which can allow the motor shaft 520 topass through for contacting the filament. The hollow conduit 540 caninclude a partial cut portion 535, which can accept the rotatablebearing 530 having a bearing shaft 537 for contacting the filament. Thecut portions 525 and 535 can be slightly larger than a diameter of thehobbed motor shaft 520 and the bearing 530, respectively, for allowingthe motor shaft and the bearing to drive the filament along the hollowconduit. The cut portion 525 for the motor shaft can cut through thehollow conduit, e.g., by a drill bit. The cut portion 535 for the motorshaft can be a partial cut, e.g., not cutting through as the cut portion525, but cutting only a part of the hollow conduit. The partial cut 535can have flanges 539, formed due to the partial cut, e.g., not cuttingthrough the hollow conduit. The flanges 539 can assist in keeping therotatable bearing in place, e.g., not sliding along the shaft 537 topositions away from the filament 510.

In some embodiments, the hollow conduit can include holes, for example,to increase a thermal isolation from the heated chamber to the motorshaft. A fan can be included, for blowing passing the holes and thehollow conduit, further reducing a temperature at the motor shaft.

In some embodiments, a force can be applied to push the followerelement, e.g., the rotatable bearing 530 relative to the motor shaft520. The force can be used to increase a friction between the motorshaft and the filament, which can prevent slippage of the filament. Asshown, a force 533 can be used to push the rotatable bearing against themotor shaft. Alternatively, a force can be applied to the motor to pushthe motor shaft against the rotatable bearing.

FIG. 6 illustrates a flow chart for filament delivering according tosome embodiments. Operation 600 provides a hollow conduit for acceptinga filament. Operation 610 forms a first cut in the conduit for passing afilament driving assembly, wherein the filament driving assembly iscoupled to the filament for driving the filament along the conduit. Thefirst cut can be a through cut, for example, by drilling through thehollow conduit at a side. The first cut can cut to the hollow portion ofthe hollow conduit, exposing the hollow interior, or exposing a portionof the filament if the filament is placed in the hollow conduit. Thefirst cut can be slightly larger than a diameter of the hobbed portionof a motor shaft, or slightly larger than a diameter of a gear coupledto a motor shaft.

Operation 620 forms a second cut in the conduit for passing a rollingassembly, wherein the rolling assembly is coupled to the filament forrolling the filament along the conduit. The second cut can be a throughcut, for example, by drilling through the hollow conduit at a side. Thesecond cut can cut to the hollow portion of the hollow conduit, exposingthe hollow interior, or exposing a portion of the filament if thefilament is placed in the hollow conduit.

The second cut can be a partial cut, for example, by cutting at a sideof the hollow conduit, while leaving flanges around the partial cut. Forexample, the rolling assembly can include a rotatable bearing having abearing thickness less than an outside diameter of the hollow conduit.The second cut can be a cut having a width slightly larger than thebearing thickness. Since the bearing thickness is smaller than theoutside diameter of the hollow conduit, the second cut can leave flangesin the hollow conduit around the bearing.

The second cut can cut to the hollow portion of the hollow conduit,exposing the hollow interior, or exposing a portion of the filament ifthe filament is placed in the hollow conduit.

Operation 630 pushes the rolling assembly toward the filament. Forexample, a spring assembly can be used for pushing the rolling assemblytoward the filament. Alternatively, the filament can be pushed towardthe rolling assembly.

Operation 640 wherein the roller assembly is optionally configured to beconstrained by the conduit.

In some embodiments, holes can be formed on the hollow conduit. A springassembly can be incorporated for pushing the hollow conduit against thefilament driving assembly. Support elements can be added around thehollow conduit, for example, for supporting the hollow conduit and/orsupporting the filament driving assembly, such as a motor.

In some embodiments, the present invention discloses a novel filamentdelivery assembly to deliver a filament, together with a print headincorporating the filament delivery assembly. The filament deliveryassembly can include a filament driving assembly, which can include anactive drive element, such as a motor rotating a hobbed shaft, and anactively follower element, such as a rotatable bearing or a rotatablehobbed shaft or gear that can be coupled to the active drive element formoving in synchronization with the active drive element.

FIG. 7A-7D illustrate a configuration for a filament delivery assemblyaccording to some embodiments. A filament delivery assembly 700 can beused in a print head, including a heated chamber 750.

A filament delivery assembly 700 can include a filament driving assembly720, which can include an active drive element such as a motor 722driving a hobbled shaft or a gear shaft. The filament driving assemblycan include a coupled follower element, such as a rotatable element suchas a bearing, a hobbed shaft or a gear 730. The follower element can becoupled to the active drive element, for example, by a belt 780. Theactive drive element can drive the filament 710 along a filament guidingassembly. The active drive element can also drive the follower element,which can assist in driving the filament in a same direction as theactive drive element. If the follower element has a rough surface, therecan be less slippage, and the follower element 730 can be considered asactively driving the filament, with the power derived from the activedrive element 920.

A filament delivery assembly 700 can be include a filament guidingassembly, which can include a hollow conduit 740. The hollow conduit 740can include a cut portion 725, which can allow the motor shaft 720 topass through for contacting the filament. The hollow conduit 740 caninclude another cut portion 735, which can allow the rotatable followerelement 730 to pass through for contacting the filament. The cutportions 725 and 735 can be slightly larger than a diameter of thehobbed motor shaft 720 and the bearing 730, respectively, for allowingthe motor shaft and the bearing to drive the filament along the hollowconduit. The cut portions can cut through the hollow conduit, e.g., by adrill bit.

When the motor rotates, the filament can be pulled into the hollowconduit from the input opening. The movement of the filament can rotatethe rotatable bearing. The motor can also push the filament, along thehollow conduit, toward the heated chamber. When the motor rotates, themotor can drive the belt, which can rotate the follower element tofurther drive the filament.

In some embodiments, the hollow conduit can include holes, for example,to increase a thermal isolation from the heated chamber to the motorshaft. A fan can be included, for blowing passing the holes and thehollow conduit, further reducing a temperature at the motor shaft.

In some embodiments, a force can be applied to push the followerelement, e.g., the rotatable follower element 730 relative to the motorshaft 720. The force can be used to increase a friction between themotor shaft and the filament, which can prevent slippage of thefilament. As shown, a force 733 can be used to push the rotatablefollower element against the motor shaft. Alternatively, a force can beapplied to the motor to push the motor shaft against the rotatablefollower element.

FIGS. 8A-8B illustrate flow charts for filament delivering according tosome embodiments. In FIG. 8A, operation 800 actively drives a filamentin two or more locations. For example, two active drive elements can beused to drive the filament in two opposite locations. One active driveelement can be coupled to the other active drive element, e.g., therecan be one motor driving two active drive elements. Each of the twoactive drive elements can include a rough surface contacting thefilament, thus when rotating, the active drive elements can move thefilament by gripping the filament.

Two active drive elements can be independent of each other, e.g., therecan be two motors, each motor driving a hobbed shaft or a gear shaft.

In FIG. 8B, operation 820 provides a hollow conduit for accepting afilament. Operation 830 forms a first cut in the conduit for passing afilament driving assembly, wherein the filament driving assembly iscoupled to the filament for driving the filament along the conduit. Thefirst cut can be a through cut, for example, by drilling through thehollow conduit at a side. The first cut can cut to the hollow portion ofthe hollow conduit, exposing the hollow interior, or exposing a portionof the filament if the filament is placed in the hollow conduit. Thefirst cut can be slightly larger than a diameter of the hobbed portionof a motor shaft, or slightly larger than a diameter of a gear coupledto a motor shaft.

Operation 840 forms a second cut in the conduit for passing anotherfilament driving assembly, or an actively follower element, e.g., afollower element that is coupled to an active drive element, and thefollower element can be configured to actively driving the filament. Theactively follower element is coupled to the filament for driving thefilament along the conduit. The second cut can be a through cut, forexample, by drilling through the hollow conduit at a side. The secondcut can cut to the hollow portion of the hollow conduit, exposing thehollow interior, or exposing a portion of the filament if the filamentis placed in the hollow conduit.

The second cut can be a partial cut, for example, by cutting at a sideof the hollow conduit, while leaving flanges around the partial cut. Forexample, the actively follower element can include a rotatable gearhaving a gear thickness less than an outside diameter of the hollowconduit. The second cut can be a cut having a width slightly larger thanthe gear thickness. Since the gear thickness is smaller than the outsidediameter of the hollow conduit, the second cut can leave flanges in thehollow conduit around the gear.

The second cut can cut to the hollow portion of the hollow conduit,exposing the hollow interior, or exposing a portion of the filament ifthe filament is placed in the hollow conduit.

Operation 850 couples the first filament driving assembly with thesecond filament driving assembly, or couples the filament drivingassembly with the actively follower element. The coupling is configuredso that the filament driving assemblies are configured to drive thefilament in a same direction. In some embodiments, the coupling isconfigured to drive the filament is a same speed.

In some embodiments, the active drive element and the actively followerelement can be pushed against each other with the filament in between.For example, a spring assembly can be used for pushing the active driveelement and/or the actively follower element toward the filament.

In some embodiments, holes can be formed on the hollow conduit. A springassembly can be incorporated for pushing the hollow conduit against thefilament driving assembly. Support elements can be added around thehollow conduit, for example, for supporting the hollow conduit and/orsupporting the filament driving assembly, such as a motor.

In some embodiments, the present invention discloses a novel filamentdelivery assembly to deliver a filament, together with a print headincorporating the filament delivery assembly. The filament deliveryassembly can include a filament driving assembly, which can include twoor more independent active drive elements, such as motors rotating ahobbed shaft or gear. The two active drive elements can be pushedtogether for an optimal friction to the filament.

FIG. 9A-9D illustrate a configuration for a filament delivery assemblyaccording to some embodiments. A filament delivery assembly 900 can beused in a print head, including a heated chamber 950.

A filament delivery assembly 900 can include a first filament drivingassembly 920, which can include an active drive element such as a motor922 driving a hobbled shaft or a gear shaft. The filament drivingassembly can include a second filament driving assembly 930, which caninclude an active drive element such as a motor 932 driving a hobbledshaft or a gear shaft. The first and second active drive elements can beindependent of each other, e.g., each one with its own motor driving ahobbed or gear shaft. The active drive elements 920 and 930 can drivethe filament 910 along a filament guiding assembly, such as driving thefilament in a same direction and/or same speed. As shown, motors 922 and932 can be arranged in opposite direction, with the shafts facing eachother. Thus the two shafts can be placed close to each other, such ascloser than the diameter of the filament, which can be 1.75 mm or 3 mm.

A filament delivery assembly 900 can be include a filament guidingassembly, which can include a hollow conduit 940. The hollow conduit 940can include a cut portion 925, which can allow the motor shaft 920 topass through for contacting the filament. The hollow conduit 940 caninclude another cut portion 935, which can allow the motor shaft 930 topass through for contacting the filament. The cut portions 925 and 935can be slightly larger than a diameter of the hobbed motor shafts 920and 930, for allowing the motor shafts to drive the filament along thehollow conduit. The cut portions can cut through the hollow conduit,e.g., by a drill bit.

When the motors rotates, the filament can be pulled into the hollowconduit from the input opening. The motors can also push the filament,along the hollow conduit, toward the heated chamber.

In some embodiments, the hollow conduit can include holes, for example,to increase a thermal isolation from the heated chamber to the motorshaft. A fan can be included, for blowing passing the holes and thehollow conduit, further reducing a temperature at the motor shaft.

In some embodiments, a force can be applied to push the active driveelements together, e.g., the first active drive element 920 relative tothe second active drive element 930. The force can be used to increase afriction between the motor shafts and the filament, which can preventslippage of the filament.

In some embodiments, the present invention discloses systems and methodshaving an applied force on two active drive elements of a filamentdelivery assembly. Two active drive elements can be linearly orrotatably pushing together against a filament.

FIGS. 10A-10C illustrate configurations for a filament delivery assemblyaccording to some embodiments. In FIG. 10A, a filament delivery assemblycan include a first filament driving assembly 1020, which can include anactive drive element such as a motor 1020A driving a hobbled shaft or agear shaft. The filament driving assembly can include a second filamentdriving assembly 1030, which can include an active drive element such asa motor 1030A driving a hobbled shaft or a gear shaft. The first andsecond active drive elements can be independent of each other, and canbe configured to face each other, with a filament guiding assembly 1040and a filament 1010 located in between. A force 1070 can be applied toeither filament drive assembly, for example, to maintain an optimalfriction between the filament drive assemblies and the filament.

FIG. 10B shows a configuration for linearly controlling a relativeposition of the two active drive elements. A first motor 1022A can havea hobbed or gear shaft 1022. The motor 1022A can be mounted to a support1052. A second motor 1032A can have a hobbed or gear shaft 1032. Themotor 1032A can be mounted to a support 1062. Flexible elements, orresilient elements, or spring elements 1082 can be placed between thesupports 1052 and 1062, which sandwich a filament 1012 and hollowconduit 1042, e.g., a filament guiding assembly. For example, a hollowconduit 1042 can be loosely place between the two supports 1052 and1062. Alternatively, the hollow conduit 1042 can be fixed coupled to onesupport, and can move inside the other support.

Forces 1072, such as screws, can be applied to the two supports forsecuring the two supports together. The force can be adjusted, since thetwo supports can resist the applied forces through the flexibleelements, or resilient elements, or spring elements 1082. Optimal forcescan be used, to provide appropriate driving force on the filament.

FIGS. 10C (a)-(b) show a configuration for rotatingly controlling arelative position of the two active drive elements. A first motor 1024Acan have a hobbed or gear shaft 1024. The motor 1024A can be mounted toa support 1054. A second motor 1034A can have a hobbed or gear shaft1034. The motor 1034A can be mounted to a support 1064.

A hinge element 1086 can couple the two supports, for example, to form apivot point so that one support can rotate 1076 relative to the othersupport.

A flexible element, or resilient element, or spring element 1084 can beplaced between the supports 1054 and 1064, which sandwich a filament1014 and hollow conduit 1044, e.g., a filament guiding assembly. Forexample, a hollow conduit 1044 can be loosely place between the twosupports 1054 and 1064. Alternatively, the hollow conduit 1044 can befixed coupled to one support, and can move inside the other support.

A force 1074, such as screws, can be applied to the two supports forsecuring the two supports together. The force can be adjusted, since thetwo supports can resist the applied forces through the flexibleelements, or resilient elements, or spring elements 1084. Optimal forcescan be used, to provide appropriate driving force on the filament.

FIGS. 11A-11B illustrate flow charts for filament delivering accordingto some embodiments. In FIG. 11A, operation 1100 actively drives afilament in two or more locations using two independent movementmechanisms. For example, two active drive elements can be used to drivethe filament in two opposite locations. An active drive element caninclude a rough surface contacting the filament, such as a hobbed shaftor a gear shaft of a motor, together with a driving component, such as amotor. Thus when the motor runs, the rough surface of the shaft can movethe filament by gripping the filament. Two active drive elements can beindependent of each other, e.g., there can be two motors, each motordriving a hobbed shaft or a gear shaft.

In FIG. 11B, operation 1120 provides a hollow conduit for accepting afilament. Operation 1130 forms a first cut in the conduit for passing afilament driving assembly, wherein the filament driving assembly iscoupled to the filament for driving the filament along the conduit. Thefirst cut can be a through cut, for example, by drilling through thehollow conduit at a side. The first cut can cut to the hollow portion ofthe hollow conduit, exposing the hollow interior, or exposing a portionof the filament if the filament is placed in the hollow conduit. Thefirst cut can be slightly larger than a diameter of the hobbed portionof a motor shaft, or slightly larger than a diameter of a gear coupledto a motor shaft.

Operation 1140 forms a second cut in the conduit for passing anotherfilament driving assembly, or an actively follower element, e.g., afollower element that is coupled to an active drive element, and thefollower element can be configured to actively driving the filament. Theactively follower element is coupled to the filament for driving thefilament along the conduit. The second cut can be a through cut, forexample, by drilling through the hollow conduit at a side. The secondcut can cut to the hollow portion of the hollow conduit, exposing thehollow interior, or exposing a portion of the filament if the filamentis placed in the hollow conduit.

The second cut can cut to the hollow portion of the hollow conduit,exposing the hollow interior, or exposing a portion of the filament ifthe filament is placed in the hollow conduit.

The two filament driving assemblies can be independent of each other.For example, a first motor and a second motor can be used to drive afirst hobbed shaft and a second hobbed shaft, respectively, forindependently driving the filament.

Operation 1150 optionally adjusts a position of the first filamentdriving assembly with respect to the second filament driving assembly.The two filament driving assemblies can be pushed against each otherwith the filament in between, e.g., the first filament driving assemblycan contact the filament at one location, and the second filamentdriving assembly can contact the filament at an opposite location. Thepushing force can be adjusted, for example, by a flexible element, aresilient element, or a spring element.

In some embodiments, holes can be formed on the hollow conduit. A springassembly can be incorporated for pushing the hollow conduit against thefilament driving assembly. Support elements can be added around thehollow conduit, for example, for supporting the hollow conduit and/orsupporting the filament driving assembly, such as a motor.

In some embodiments, the two active drive elements can significantlyincrease the driving force for pulling the filament from the filamentroll and for pushing the filament through the heated chamber. Not onlythe driving force increase due to the doubling of the active driveelements, the force can further increase due to the pressing of thehobbed shafts, which can increase the friction force, leading to anincrease in the driving force.

The increase in driving force can be beneficial for soft filamentmaterials, such as rubber. For soft filaments, one active driving forcecan deform the filament, leading to slippage. Two active driving forcescan increase the grip of the rough motor shafts with the soft filament,leading to securely moving the soft filaments toward the heated chamber.

The increase in driving force can be beneficial for irregular filaments,such as filaments having variable in diameter dimension. For portions ofthe filament having smaller diameter, one active driving force can slip,since the gap between the hobbed shaft and the support bearing can beconstant, but the filament diameter is reduced. Two active drivingforces can increase the grip of the rough motor shafts with thefilament, even at the smaller diameter portions, leading to securelymoving the irregular filaments toward the heated chamber.

In some embodiments, the present invention discloses methods and systemshaving an acoustic sensor assembly for detecting and/or correctingconditions of a system having a moving mechanism. For example, a motor,under normal operating conditions, can generate certain sound signals.Under abnormal conditions, such as having too high a load or running toohigh a speed, the motor can generate different sound signals. Thus byreceiving and analyzing the acoustic signals emitted by the motor, suchas intensity and frequency of the emitted sound, a controller can detecterrors, e.g., conditions in which the motor does not operate normally oroptimally. Upon detecting, the controller can correct the errors, suchas by changing an operating condition of the motor, to return the motorto the normal or optimal operating conditions.

In some embodiments, the moving mechanism can generate different soundcharacteristics when contacting an object. Thus the acoustic sensorassembly can be used to detect contact conditions of a moving mechanism,such as detecting when the moving mechanism reaches an obstacle or whenthe moving mechanism reaches a boundary. The contact detection processcan be used for a zeroing operation, e.g., a distance between twoobjects can be set to zero when the acoustic sensor assembly detects adifferent acoustic signal, signifying that the two objects are incontact. The zeroing operation can be used in zeroing a print head to aplatform, or to leveling a platform in a 3d printer system.

In some embodiments, the moving mechanism can include a motor, ahydraulic cylinder, a pneumatic cylinder, a fan or a blower. The movingmechanism can also include a vibrating assembly, such as a piezoassembly or a sound generating assembly, such as a speaker.

FIGS. 12A-12C illustrate acoustic sensor configurations according tosome embodiments. In FIG. 12A, a system can include a moving mechanism1220, such as a motor assembly, a piezo assembly, or a speaker assembly,which can be in operation, and can emit acoustic signals 1230. Themoving mechanism 1220 can include a sound amplifier, for example, toamplify any sound emitted by the moving mechanism.

An acoustic sensor assembly can include an acoustic sensor 1210, whichcan receive the acoustic signals 1230 and send the acoustic signals to acontroller 1240. The controller can analyze the acoustic signals, suchas determining the amplitude, frequency, cyclic nature of the signals,and other information. The analyzed information can be used to determinea condition of the system, such as an abnormal operating condition ofthe moving mechanism, or a contact information of a moving mechanism toan object. The analyzed information can be used as inputs to othercomponents of the system, for example, to a motor to adjust a speed ifthe analyzed information concludes that the speed of the motor isimproper, which is the cause of the received acoustic signals. Theanalyzed information can be used as inputs to identify that a print headhas touched a platform, and a controller can initialize the position ofthe print head, e.g., setting the position of the print head to zero.The analyzed information can be used as inputs to leveling a platform,for example, by changing a height of the platform so that a print headcan contact the platform at multiple places.

In some embodiments, a system can include multiple sound generators,such as multiple motors, piezo assemblies, or fan components. Thusmultiple acoustic sensors can be disposed in a system, for example, toidentify the source of the sound emission.

In FIG. 2B, sensors can be placed near the potential sound generators.For example, a sensor 1211 can be placed near a motor 1221, and a sensor1212 can be placed near a motor 1222. The sensors can be shielded fromother sound generators, for example, to receive mostly signals from theintended sound generators.

When a controller 1241 receives a signal, it can identify the source ofthe signal by knowing the sound generator located near the sensor. Forexample, if the controller receives a signal from sensor 1211, thesource of the emitted signal can be the motor 1221. In some cases,signals from nearby motors can reach other sensors. For example, sensor1211 can receive signals from motor 1222. A threshold cut off can beused to remove the erroneous information. A comparison of signals can beused to determine the threshold value. For example, a signal amplitudefrom motor 1211 can be compared with a signal amplitude from motor 1222,and a threshold can be set to, for example, a value between the twosignal amplitudes. Thus if a signal received by sensor 1211 is lowerthan the threshold value, the signal can be ignored.

In FIG. 12C, multiple sensors can be placed around the system, and thesound sources can be identified by relative intensities received by themultiple sensors, such as by a triangulation process. A system caninclude multiple sound sources, such as motors 1225 and 1226. Multiplesensors 1215 and 1216 can be placed around the system. When a controller1245 receives signals from these sensors 1215 and 1216, the source ofthe sound can be calculated by the relative intensities of the receivedsignal. For example, if the motor 1225 is the sound source, sensor 1215can receive a signal 1235, which can be higher, e.g., stronger orlouder, than the signal 1236 received by the sensor 1216.

FIGS. 13A-13C illustrate flow charts for acoustic signal configurationsaccording to some embodiments. In FIG. 13A, operation 1300 senses anacoustic signal from a movement assembly. The movement assembly caninclude a motor, a hydraulic assembly, a pneumatic assembly, a fan, or avibration assembly such as a piezo component. The signal can beanalyzed, for example, calculating a frequency spectrum from thereceived time evolution sound intensity. Operation 1310 detects anoperation condition of the movement assembly. The intensity andfrequency of the signal can be used to determine a cause of the signal.For example, a high pitch sound can be caused by a motor having highload, such as a mill bit stuck in a cut material. Or a loud noise canindicate that a fan can be broken. A sudden change in intensity canindicate a contact condition, such as a moving print head contacting aplatform, or a moving platform contacting a print head.

In FIG. 13B, operation 1330 senses an acoustic signal. Operation 1340determines a movement assembly that emits the acoustic signal. Theidentification of the sound source can be by proximity, e.g., locatingthe source that is closest to the sensor, or by triangulation, e.g.,calculating the location of the source by the signal intensitiesreceived by multiple sensors placed at different locations. Operation1350 adjusts an operation condition of the identified movement assembly.

In FIG. 13C, operation 1370 provides a system comprising a motor. Thesystem can be a mill machine, a lathe machine, a router system, or asystem having a hydraulic or pneumatic component. Operation 1380installs an acoustic sensor for detecting and/or adjusting an operationcondition of the system.

In some embodiments, an acoustic sensor assembly can be used fordetecting a contact condition of a system. For example, a moving objectcan approach a stationary object. An acoustic sensor assembly can beused for detecting when the moving object contacts the stationaryobject. The moving object can generate certain sound signals, which cantransmit through an air ambient to reach the acoustic sensor. Uponreaching the stationary object, the sound signal can transmit throughthe stationary object, which can have different characteristics, such ashigher intensity or higher frequency. The change in the received signalcharacteristics can signify that a contact condition is reached, e.g.,the moving object has contacted the stationary object.

In some embodiments, the moving object can include a motor, such as aprint head having an integrated motor for driving the filament. Themoving object can include a motor such as a mill head having a rotatemill bit. When rotating, the motor can emit sound.

A print head of a 3D printer can be the moving object, and a platform ofthe 3D printer can be the stationary object. A mill head of a millmachine can be the moving object, and an object to be milled of the millmachine can be the stationary object.

In some embodiments, the motor can be turned on at special conditions togenerate a noise that can be good for detection by the sensor, or goodfor a distinction when the motor contacts the object. For example, themotor can rotate back and forth at a high speed, which can generate ahigh pitch sound.

In some embodiments, a sound generator can be coupled to the movingobject, for example, in the case that the moving object does not produceany sound, such as a remote print head having a filament delivery motorplaced at a remote location. Thus the remote print head can include aheated chamber and a nozzle, together with an input coupling forreceiving a filament. A sound generator, such as a piezo dielectriccomponent, can be coupled to the silent moving object, e.g., the movingobject that does not generate any sound.

In some embodiments, a sound generator, such as a piezo element, aspeaker or an amplifier, can be coupled to the stationary object, forexample, in the case that the moving and stationary objects do notproduce any sound.

In some embodiments, the acoustic sensor can be placed on the objectthat does not produce the sound, such as on the stationary object. Themoving object can generate a sound, transmitting through the air toreach the sensor. When contacting the stationary object, the sound cantransmit through the stationary object to reach the sensor, thus thesound signal can have a detectable change.

FIGS. 14A-14D illustrate contact sensing configurations using anacoustic sensor assembly according to some embodiments. In FIG. 14A, aprint head 1400 of a system, such as a 3D printer system, can be placedfacing a platform 1450. The print head can include a motor 1420 rotatinga hobbed shaft or a gear shaft, e.g., a shaft with a rough surface. Therough surface can be in contact with a filament, for driving thefilament into a heated chamber for delivering to the platform forprinting objects.

The print head can be coupled to a z moving mechanism for moving theprint head in a perpendicular direction with respect to the platform.The print head can be coupled to other moving mechanisms, such as xymoving mechanisms to move the print head in directions parallel to theplatform. A relative position of the print head to the platform can beused for locating the print head at correct z positions. The print headcan undergo a zeroing operation, e.g., zeroing the distance between theprint head and the platform. For example, the print head can move towardthe platform. When the print head contacts the platform, the distancebetween the print head and the platform can be zero.

In some embodiments, an acoustic sensor assembly can be used to assistin the zeroing operation, such as determining the position when theprint head contacts the platform. An acoustic sensor 1410 can beprovided to the 3D printer. The acoustic sensor can be coupled to acontroller 1440, for example, by wire connection or wireless connection.The acoustic sensor 1410 can be placed in different locations in the 3Dprinter system, for example, at a location near the platform, at alocation near a floor space, at a location near a ceiling space, at alocation near a wall space. In some embodiments, the acoustic sensor canbe placed at the platform, e.g., in contact with the platform, so thatthe acoustic signal can transfer through the platform to the acousticsensor. Sound can travel better in solid ambient, thus higher signalscan be achieved when the print head contacts the platform with thesensor also contacting the platform.

In operation, the print head 1400 can approach the platform 1450, forexample, by commands from a controller. The controller can keep track ofthe positions of the print head. The print head can generate an acousticsignal 1430, e.g., a sound, which can be received by the acoustic sensor1410. When the print head is separated from the platform, the acousticsignal can travel through air to reach the acoustic sensor. When theprint head touches the platform, a different acoustic signal can bereceived by the acoustic sensor, for example, due to the contact of theprint head and the platform, which can change the characteristics of theemitted sound. Also, the acoustic signal can travel through the platformto reach the sensor, thus the received signal can be different than asame signal transmitted through air.

The difference in the received signal can identify the position that theprint head contacts the platform. The controller then can set theposition of the print head to be zero, which can served as a referencefor other positions of the print head, relative to the platform.

In some embodiments, the print head can be configured to generate anacoustic signal, e.g., generating noise or sound. The print head canhave a motor, such as the motor 1420 that can be used for filamentdelivery, e.g., for pushing a filament into a heated chamber for meltingthe filament. The motor can be configured or operated in a vibratorymode, which can generate an acoustic signal. For example, the motor canrotate back and forth at a high frequency.

In some embodiments, a motor in a print head can operate in a vibratorymode or an oscillation mode. The motor can receive commands from acontroller to continue turning back and forth, e.g., turning clockwiseand then turning counterclockwise, or to turn clockwise orcounterclockwise at a high speed. The selection can depend of whether afilament is present. For example, if there is a filament in the printhead, then turning back and forth can be used, for not running thefilament through the print head. The angle of turning in one directioncan be small, such as less than 30 degrees, in order not to push or pullthe filament for a large distance. If there is no filament, then onedirection turning can be used.

In FIG. 14B, a rotating head 1405 of a system, such as a mill head of aCNC milling system or a router head of a router system, can be placedabove an object to be processed 1455. The rotating head can include amotor 1425 rotating a bit, such as a mill bit for milling, or a drillbit for drilling. The rotating bit can contact object, and sharp edgesof the rotating bit can cut into the object, such as the drill bit candrill a hole in the object, or the mill bit can mill a pattern on theobjects.

The rotating head can be coupled to a z moving mechanism for moving therotating head in a perpendicular direction with respect to the object.The rotating head can be coupled to other moving mechanisms, such as xymoving mechanisms to move the rotating head in directions parallel tothe object. A relative position of the rotating head to the object canbe used for locating the rotating head at correct z positions. Therotating head can undergo a zeroing operation, e.g., zeroing thedistance between the rotating head and the object. For example, therotating head can move toward the object. When the rotating headcontacts the object, the distance between the rotating head and theobject can be zero.

In some embodiments, an acoustic sensor assembly can be used to assistin the zeroing operation, such as determining the position when therotating head contacts the object. An acoustic sensor 1415 can beprovided to the system. The acoustic sensor can be coupled to acontroller 1445, for example, by wire connection or wireless connection.The acoustic sensor 1415 can be placed in different locations in thesystem, for example, at a location near the object, at a location near afloor space, at a location near a ceiling space, at a location near awall space. In some embodiments, the acoustic sensor can be placed atthe object, e.g., in contact with the object, so that the acousticsignal can transfer through the object to the acoustic sensor. Sound cantravel better in solid ambient, thus higher signals can be achieved whenthe rotating head contacts the object with the sensor also contactingthe object.

In operation, the rotating head 1405 can approach the object 1455, forexample, by commands from a controller. The controller can keep track ofthe positions of the rotating head. The rotating head can generate anacoustic signal 1435, e.g., a sound, which can be received by theacoustic sensor 1415. When the rotating head is separated from theobject, the acoustic signal can travel through air to reach the acousticsensor. When the rotating head touches the object, a different acousticsignal can be received by the acoustic sensor, for example, due to thecontact of the rotating head and the object, which can change thecharacteristics of the emitted sound. Also, the acoustic signal cantravel through the object to reach the sensor, thus the received signalcan be different than a same signal transmitted through air.

The difference in the received signal can identify the position that therotating head contacts the object. The controller then can set theposition of the rotating head to be zero, which can served as areference for other positions of the rotating head, relative to theobject.

In some embodiments, the rotating head can be configured to generate anacoustic signal, e.g., generating noise or sound. The rotating head canhave a motor, such as the motor 1425 that can be used for rotating therotating head, e.g., for cutting the object. The motor can be configuredor operated in a vibratory mode, which can generate an acoustic signal.For example, the motor can rotate back and forth at a high frequency.

In some embodiments, a motor in a rotating head can operate in avibratory mode or an oscillation mode. The motor can receive commandsfrom a controller to continue turning back and forth, e.g., turningclockwise and then turning counterclockwise, or to turn clockwise orcounterclockwise at a high speed. The angle of turning in one directioncan be small, such as less than 30 degrees.

In FIG. 14C, operation 1480 detects a contact of a movement assembly toan object based on a change in a received acoustic signal. The movementassembly can include an assembly having a movable component, such as amotor, a fan, or a vibration element. The movement assembly can generatenoise, e.g., acoustic signal, for example, due to the movable component.In some embodiments, the movable component can be configured to makenoise, such as receiving commands from a controller to run back andforth at a high frequency, e.g., the number of running back and forthcycles can be high, such as more than 10 per minute, more than 50, 100,500, or 1000 per minutes. A change in the noise characteristics, such asintensity change or frequency change, can indicate that the movementassembly has contacted the object.

In FIG. 14D, operation 1482 moves a movement assembly to approach anobject. The movement assembly can include a movable component. In someembodiments, the movable component can move in a certain way, e.g.,moving in order to increase, maximize or optimize a change in theacoustic signal when the movement assembly contacts the object. Themovement of the movable component can be controlled by a controller,e.g., the movement is generated by commands from the controller, for thecontacting process, and may not be a normal movement of the movablecomponent. For example, the movement can be configured to vibrate themovable component, such as by moving back and forth, rotating clockwiseand counterclockwise, or rotating at a speed that can generate a sound.

Operation 1483 determines a position of the movement assembly whendetecting a change in a received acoustic signal.

FIGS. 15A-15C illustrate contact sensing configurations using anacoustic sensor assembly according to some embodiments. In FIG. 15A, acomponent 1500 of a system, such as a print head of a 3D printer system,can be positioned facing an object 1550, such as a platform.

An acoustic sensor assembly can be used to assist in a zeroingoperation, such as determining the position when the component contactsthe platform. An acoustic sensor 1510 can be provided to the system. Theacoustic sensor can be coupled to a controller 1540, for example, bywire connection or wireless connection. The acoustic sensor 1510 can beplaced in different locations in the system, including at the platform,e.g., in contact with the platform.

A sound generator 1520, such as a vibration assembly having a piezoelement, or an amplifier having an oscillator circuit, can be coupled tothe component 1500.

In operation, the component 1500 can approach the platform 1550, forexample, by commands from a controller. An acoustic signal 1530, e.g., asound can be generated, which can be received by the acoustic sensor1510. When the component touches the platform, a different acousticsignal can be received by the acoustic sensor.

The difference in the received signal can identify the position that thecomponent contacts the platform. The controller then can set theposition of the component to be zero, which can served as a referencefor other positions of the component, relative to the platform.

In FIG. 15B, operation 1580 detects a contact of a first object having asound generator to a second object based on a change in a receivedacoustic signal.

The first object can include an assembly having a sound generator, suchas a motor, a fan, a vibration element, or a sound circuit, e.g., acircuit that can transmit sound, such as an oscillator circuit coupledto a speaker.

In FIG. 15C, operation 1582 moves a first object having a soundgenerator to approach a second object. The first object can include anassembly having a sound generator, such as a motor, a fan, a vibrationelement, or a sound circuit, e.g., a circuit that can transmit sound,such as an oscillator circuit coupled to a speaker.

Operation 1583 determines a position of the first object when detectinga change in a received acoustic signal.

In some embodiments, the present invention discloses methods and systemsfor leveling an object based on an acoustic sensor assembly. A system,such as a 3d printer, a cnc machine, or a router machine can have aplatform level with respect to a head. For example, a platform of a 3dprinter can be positioned so that a print head can be at a same height,e.g., having a same z position, when the print head moves in paralleldirections, e.g., in x and y directions. The platform parallel can bemake leveling with the print head, e.g., raising or lowering portions ofthe platform so that the platform plane is parallel with the plane inwhich the print head is movable.

FIGS. 16A-16C illustrate a leveling configuration using an acousticsensor assembly according to some embodiments. In FIG. 16A, a component1600 of a system, such as a print head of a 3D printer system, can bepositioned facing an object 1650, such as a platform.

An acoustic sensor assembly can be used to assist in a zeroingoperation, such as determining the position when the component contactsthe platform. An acoustic sensor 1610 can be provided to the system. Theacoustic sensor can be coupled to a controller 1640, for example, bywire connection or wireless connection. The acoustic sensor 1610 can beplaced in different locations in the system, including at the platform,e.g., in contact with the platform.

A sound generator 1620, such as a vibration assembly having a piezoelement, or an amplifier having an oscillator circuit, can be optionallycoupled to the component 1600. Alternatively, a movable component of thecomponent 1600 can be configured to generate sound, such as a motorrotating back and forth at a high frequency, or rotating with a speed tomake noise.

In operation, the component 1600 can approach the platform 1650 todetermine a z position that the component contacts the platform. Thecomponent 1600 can determine different z positions at differentlocations of the platform. If the z positions are not the same, then theplatform is not leveled. Appropriate areas of the platform can be movedin the z direction, in appropriate amount so that the z positions arethe same.

Alternatively, the component 1600 can approach the platform 1650 at afirst location to determine a contact position. The z position of thecomponent 1600 can be set to zero, e.g., a zeroing process. Thecomponent can move to a second location of the platform, e.g., moving ina parallel direction, such as x or y direction. A contact position atthe second location can be determined. The platform can be adjusted atthe second location, so that the contact position at the second locationis zero. The process can continue for other locations, such as at atleast 3 locations, to leveling the platform with respect to thecomponent 1600.

In FIG. 16B, operation 1680 levels a platform using an acoustic sensingassembly. The platform can be adjusted in height, e.g., in a directionperpendicular to the movements of the moving head, such as a print heador a mill head, so that the moving head can registered a zero positionwhen contacting the platform, at multiple locations of the platform. Theacoustic sensor can be used to determine the zero positions.

In FIG. 16C, operation 1682 detects offset values at different portionsof a platform based on a change in a received acoustic signal 1630 ateach portion. Operation 1683 levels the platform using the offsetvalues.

FIG. 17 illustrates a 3D printer configuration according to someembodiments. A printer 1700 can include a platform 1740 for supporting aprinted object 1710. The platform 1740 can move in a z direction, forexample, up and down, to bring the platform 1740 closer to a printerhead 1750. The printer head 1750 can move in a lateral direction, suchas an x direction. For example, a moving mechanism 1752 can beconfigured to move the printer head 1750 in the x direction. Theplatform can be configured to move in another lateral direction, such asan y direction. For example, a moving mechanism 1752 can be configuredto move the platform in the y direction.

Other moving mechanisms can be used, such as a x-y table configured tomove the printer head. For example, a printer head can move in lateraldirections, such as x and y directions. A first moving mechanism 1756can be configured to move the printer head in the x direction. A secondmoving mechanism 1754 can be configured to move the first movingmechanism in the y direction. In addition, the platform can bestationary, with the printer head moves in the z direction.

A controller 1720 can be included to move the printer head according toa pattern for printing on the platform. Other components can beincluded, such as a filament reservoir.

An acoustic sensor 1760 can be included. The acoustic sensor can includean element that can receive an acoustic signal, such as a microphone.The acoustic sensor can be coupled to the controller, for example, tosupply the received acoustic signals to the controller, for assist inrunning the 3D printer. For example, the acoustic sensor can be used forperform zeroing operation between the print head 1750 and the platform1740. The acoustic sensor can also be used to level the platform, withrespect to the print head.

FIGS. 18A-18D illustrate configurations for 3D printers according tosome embodiments. In FIG. 18A, operation 1800 installs an acousticsensor to a 3D printer. The acoustic sensor can be placed in a locationin the 3D printer, such as at a location that can receive acousticsignals from movement mechanisms, e.g., motors, and from the print headof the 3D printer. The acoustic sensor can be installed in contact withthe platform of the 3D printer. The acoustic sensor can be coupled witha controller of the 3D printer, with the controller controlling themovement mechanisms and other sensors.

Operation 1810 detects and/or adjusts an operation condition of the 3Dprinter based on a signal from the acoustic sensor. For example, theacoustic sensor can detect error conditions of the movement mechanisms,such as motors running with excessive load. The controller can correctthe error conditions, for example, by changing operating conditions ofthe motors. The acoustic sensor can be used for zeroing the print headwith respect to the platform. The acoustic sensor can be used forleveling the platform.

In FIG. 18B, operation 1830 zeros a distance between a print head and aplatform of a 3D printer based on a signal from an acoustic sensor.

In FIG. 18C, operation 1850 levels a platform of a 3D printer based on asignal from an acoustic sensor

In FIG. 18D, operation 1870 detects and/or adjusts an operationcondition of a motor in a D printer based on a signal from an acousticsensor

In some embodiments, the present invention discloses methods and systemsfor novel flexible components, having a carbon fiber mesh coupling witha flexible membrane. A carbon fiber mesh can be incorporated in a 3Dprinted layer of a flexible material, and excess portions of the carbonfiber mesh can be trimmed, for example, by a laser.

In some embodiments, a carbon fiber mesh can be placed on a 3D printingplatform, and a flexible layer can be printed on the carbon fiber mesh.A laser can be used to cut the carbon fiber mesh, for example, along acontour of the flexible layer. Other components can be added, such as ahard layer for supporting the flexible layer.

Other configurations to incorporate a carbon fiber mesh to a flexiblelayer can be used, such as providing a flexible layer before placing acarbon fiber mesh on the flexible layer. Another flexible layer can beadded on the carbon fiber mesh, together with hard layers for support.Alternatively, a support structure can be provided, and a carbon fibermesh can be placed at desired locations on the support structure. Aflexible layer can be printed on the carbon fiber mesh. The carbon fibermesh can be trimmed, for example, to conform to the shape of theflexible layer.

FIGS. 19A-19B illustrate a flexible layer having carbon fiber meshaccording to some embodiments. A carbon fiber mesh reinforced flexiblelayer 1900 in FIG. 19A can include a flexible layer 1910 or 1915 havinga carbon fiber mesh 1920 or 1925 incorporated therein. The carbon fibermesh can include parallel lines disposed at an angle, for example,perpendicular as shown, with respect to a rotating line or point 1935.The reinforced layer 1900 can be bent 1930 or rotated, for example,around any fixed point 1935 in FIG. 19B.

FIGS. 20A-20B illustrate configurations for carbon fiber mesh reinforcedflexible layers according to some embodiments. FIG. 20A shows patternsof carbon fiber mesh, which can be incorporated in a flexible layer. Acarbon fiber mesh 2021 can be used for reinforcing a flexible layer2011. The carbon fiber mesh 2021 can have a square pattern inside theflexible layer, e.g., leaving a space 2051 at edges of the flexiblelayer. The reinforced flexible layer can flex 2031 around an axisparallel to a fiber line of the carbon fiber mesh.

In some embodiments, a carbon fiber mesh 2023 can be used forreinforcing a flexible layer 2013. The carbon fiber mesh 2023 can have asquare pattern up to the edges of the flexible layer. The reinforcedflexible layer can flex 2033 around an axis parallel to a fiber line ofthe carbon fiber mesh.

In some embodiments, a carbon fiber mesh 2025 can be used forreinforcing a flexible layer 2015. The carbon fiber mesh 2025 caninclude lines disposed at an angle with respect to an axis of rotation.The reinforced flexible layer can flex 2035 around an axis parallel to afiber line of the carbon fiber mesh.

In some embodiments, a carbon fiber mesh 2027 can be used forreinforcing a flexible layer 2017. The carbon fiber mesh 2027 can have asquare pattern, disposed at an angle with respect to an axis ofrotation. The reinforced flexible layer can flex 2037 around an axisparallel to a fiber line of the carbon fiber mesh.

FIG. 20B shows configurations of carbon fiber mesh with respect to aflexible layer. The carbon fiber mesh 2022 can be disposed inside aflexible layer 2012, e.g., in an interior portion of the flexible layeror having flexible material surrounding the carbon fiber mesh. Thecarbon fiber mesh 2024 can be at one side of a flexible layer 2014,e.g., at a top exterior surface of the flexible layer. The carbon fibermesh 2026 can be at one side of a flexible layer 2016, e.g., at a bottomexterior surface of the flexible layer. The carbon fiber mesh 2028 canbe disposed at a curve surface a flexible layer 2018, for example, dueto the flexible layer having a curve shape.

In some embodiments, the carbon fiber mesh reinforced flexible layer caninclude a hard layer for support. For example, the hard layer can formthe basic structure of a component, and the flexible layer, togetherwith the carbon fiber mesh, can form a flexible portion of thecomponent.

FIGS. 21A-21C illustrate configurations for flexible layers with supportstructures according to some embodiments. In FIG. 21A, a hinge-likecomponent can have a flexible layer 2110 with an embedded carbon fibermesh 2120. The flexible layer can move 2130, e.g., flex, around an axis2140 of movement. A hard layer 2140 can be coupled to the flexiblelayer, for example, to reinforce the flexible layer, covering theflexible layer while leaving only a portion of the flexible layer neededfor the movement.

In FIG. 21B, a joint, such as a knee joint, can include movablecomponents 2152 that can move 2132 around an axis of rotation 2142. Aflexible layer 2112 can be coupled to the movable components 2152, suchas coupled to both portions of the movable components 2152. A carbonfiber mesh 2122 can be embedded in the flexible layer. The flexiblelayer can constrain the movable components, in order to move only inintended directions. The carbon fiber mesh can reinforce the flexiblelayer, for example, against breakage of the flexible layer due tomovements out of the intended directions.

In FIG. 21C, a wing structure, such as a bird wing, can includestructural components 2154, which can include hard layers for actinglike bones n the wing structure. A flexible layer 2114 can be coupled tothe structural components 2154, which can allow movements in intendeddirection 2134. A carbon fiber mesh 2124 can be embedded in the flexiblelayer for increase strength of the flexible layer.

FIGS. 22A-22B illustrate flow charts for reinforcing flexible layerswith carbon fiber mesh according to some embodiments. In FIG. 22A,operation 2200 adds a carbon fiber mesh to a flexible layer to increasedurability. The mesh can have any configurations, such as straightlines, polygon mesh such as square mesh, triangle mesh, or diamond shapemesh. The mesh can be disposed in middle, on top, or at bottom of theflexible layer. The flexible layer can be elastic or inelastic.

In FIG. 22B, operation 2220 incorporates a carbon fiber mesh to aflexible layer. For example, a flexible layer can be formed, such asprinting, on a carbon fiber mesh. Alternatively, a carbon fiber mesh canbe applied to a flexible layer.

Operation 2230 reinforces the flexible layer with a rigid layer. Forexample, a rigid layer can be printed on a portion of the flexiblelayer. The rigid layer can be formed before, after or at a same time asflexible layer. The rigid layer can be formed on top of the flexiblelayer, or next to the flexible layer.

Operation 2240 trims the carbon fiber mesh using a laser. The trimmingprocess can be performed before or after forming the rigid layer.

FIGS. 23A-23E illustrate a process for forming a carbon fiber meshreinforce flexible layer according to some embodiments. In FIG. 23A, acarbon fiber mesh 2320 can be placed on a substrate 2370, such as aplatform of a 3d printer. In FIG. 23B, a flexible layer 2310 can beprinted on the carbon fiber mesh 2320. In FIG. 23C, a hard layer 2340can optionally be printed on the flexible layer 2310. In FIG. 23D, thecarbon fiber mesh 2320 can be trimmed, for example, to have the samesize and shape as the flexible layer. The trimming process can beperformed by a laser. In FIG. 23E, the complete carbon fiber meshreinforced flexible layer 2300 can be removed from the substrate 2370.The flexible layer can be flexed, by the flexible layer and the carbonfiber mesh.

FIGS. 24A-24E illustrate a process for forming a carbon fiber meshreinforce flexible layer according to some embodiments. In FIG. 24A, acarbon fiber mesh 2420 can be placed on a substrate 2470, such as aplatform of a 3d printer. In FIG. 24B, a flexible layer 2410 and aportion of a hard layer 2440 can be printed on the carbon fiber mesh2420. In FIG. 24C, another portion of the hard layer 2440 can optionallybe further printed on the existing portion of the hard layer 2440. InFIG. 24D, the carbon fiber mesh 2420 can be trimmed, for example, tohave the same size and shape as the flexible layer. The trimming processcan be performed by a laser. In FIG. 24E, the complete carbon fiber meshreinforced flexible layer 2400 can be removed from the substrate 2470.The flexible layer can be flexed, by the flexible layer and the carbonfiber mesh.

FIGS. 25A-25D illustrate configurations of carbon fiber mesh reinforcedflexible layers according to some embodiments. In FIG. 25A, a carbonfiber mesh reinforced flexible layer 2500 can include a carbon fibermesh 2520 placed between two flexible layers 2510 and 2570, togetherwith a hard layer 2540. A fabrication process can include printing theflexible layer 2510 on the carbon fiber mesh 2520, and then the hardlayer 2540 on the flexible layer 2510 (FIG. 25A (a)). The structure thencan be flipped over, and the second flexible layer 2570 can be printedon the carbon fiber mesh 2520 (FIG. 25A (b)). A laser trimming processcan be performed to trim the carbon fiber mesh to a desired shape andsize, either before or after printing the second flexible layer 2570.Other configurations can be used, such as adding a hard layer on theflexible layer 2570.

In FIG. 25B, a carbon fiber mesh reinforced flexible layer 2501 caninclude a carbon fiber mesh 2521 placed between two flexible layers 2511and 2571, together with hard layers 2541 and 2561. A fabrication processcan include printing the flexible layer 2511 on the carbon fiber mesh2521, and then the hard layer 2541 on the flexible layer 2511 (FIG. 25B(a)). The structure then can be flipped over, and the second flexiblelayer 2571 and the second hard layer 2561 can be printed on the carbonfiber mesh 2521 (FIG. 25B (b)). A laser trimming process can beperformed to trim the carbon fiber mesh to a desired shape and size,either before or after printing the second flexible layer 2571 or thehard layer 2561. Other configurations can be used, such as without thesecond flexible layer 2571, or with a thicker hard layer 2561.

In FIG. 25C, a carbon fiber mesh reinforced flexible layer 2502 caninclude a carbon fiber mesh 2522 placed between two flexible layers 2512and 2572, together with a hard layer 2542. A fabrication process caninclude printing the flexible layer 2512 and the hard layer 2542 on thecarbon fiber mesh 2522 (FIG. 25C (a)). The structure then can be flippedover, and the second flexible layer 2572 can be printed on the carbonfiber mesh 2522 (FIG. 25C (b)). A laser trimming process can beperformed to trim the carbon fiber mesh to a desired shape and size,either before or after printing the second flexible layer 2572. Otherconfigurations can be used, such as adding a hard layer on the flexiblelayer 2572, or having a thin hard layer 2542.

In FIG. 25D, a carbon fiber mesh reinforced flexible layer 2503 caninclude a carbon fiber mesh 2523 placed between two flexible layers 2513and 2573, together with hard layers 2543 and 2563. A fabrication processcan include printing the flexible layer 2513 and the hard layer 2543 onthe carbon fiber mesh 2523 (FIG. 25D (a)). The structure then can beflipped over, and the second flexible layer 2573 and the second hardlayer 2563 can be printed on the carbon fiber mesh 2523 (FIG. 25D (b)).A laser trimming process can be performed to trim the carbon fiber meshto a desired shape and size, either before or after printing the secondflexible layer 2573 or the hard layer 2563. Other configurations can beused, such as without the second flexible layer 2573, or with a thickerhard layer 2563.

FIG. 26 illustrates a flow chart for forming carbon fiber meshreinforced flexible layers according to some embodiments. Operation 2600disposes a carbon fiber mesh on a substrate, such as on a platform of a3D printer. The substrate can be another layer of a structure.

Operation 2610 forms a first flexible layer on a first portion of thecarbon fiber mesh. The flexible layer can be printed on the carbon fibermesh. The carbon fiber mesh can be larger than the flexible layer. Thecarbon fiber mesh can be configured so that the carbon fibers can forman angle, e.g., not parallel, to a movement axis of the completestructure, e.g., the flex movement can bend the carbon fibers. A portionof the flexible layer can be configured to cover the movement axis,e.g., the complete structure can flex around the movement axis using theflexible layer.

Operation 2620 forms a first rigid layer on at least one of a portion ofthe first flexible layer and a portion of the carbon fiber mesh. Themesh can be larger than the rigid and flexible layers. The rigid layercan be formed on a portion of flexible layer, e.g., excluding themovement axis so that the rigid layer does not hinder the movement ofthe complete structure. The rigid layer can be on a portion of theflexible layer, or the rigid layer can be formed directly on the carbonfiber mesh, e.g., the rigid layer can be adjacent to the flexibleportion. The rigid layer can be thicker than the flexible layer, forexample, to provide support to the structure.

Operation 2630 trims the carbon fiber mesh using a laser. Other tools orprocesses can be used to trim the carbon fiber mesh.

Operation 2640 optionally forms a second flexible layer on an oppositeside of the carbon fiber mesh, wherein the second flexible layer isformed on a second portion of the carbon fiber mesh.

Operation 2650 optionally forms a second rigid layer on an opposite sideof the carbon fiber mesh, wherein the second rigid layer is formed on atleast one of a portion of the second flexible layer and a portion of thecarbon fiber mesh.

FIGS. 27A-27C illustrate processes for forming carbon fiber meshreinforced flexible layers according to some embodiments. In FIG. 27A, acarbon fiber mesh reinforced flexible layer 2700 can include a carbonfiber mesh 2720 disposed between a flexible layer 2710 and a hard layer2740. The hard layer can be configured to avoid a portion of the carbonfiber mesh that can affect the movement of the structure. In FIG. 27A(a), a flexible layer 2710 can be formed, such as printed, on a platform2770. In FIG. 27A (b), a carbon fiber mesh 2720 can be placed on theflexible layer 2710. The carbon fiber mesh can be secured to theflexible layer, for example, by taping or gluing to the platform, or tothe flexible layer.

In FIG. 27A (c), a hard layer 2740 can be formed, such as printed, on aportion of the carbon fiber mesh 2720. The hard layer can be formedaround the carbon fiber mesh, to secure the carbon fiber mesh to thestructure. The hard layer can be formed avoiding potential movementareas of the carbon fiber mesh, e.g., areas 2780 of the carbon fibermesh that can undergo movement.

In FIG. 27A (d), the excess carbon fiber mesh can be trimmed 2750, forexample, by a laser. In FIG. 27A (e), a complete structure 2700 of acarbon fiber mesh reinforced flexible layer is shown, which can flex fora portion of the flexible layer without the hard layer. Otherconfigurations can be used, such as having another flexible layer on thecarbon fiber mesh between the hard layer, so that the carbon fiber meshis placed between two layers of flexible material.

In FIG. 27B, a carbon fiber mesh reinforced flexible layer 2701 caninclude a carbon fiber mesh 2721 disposed between a flexible layer 2711and two hard layers 2741 and 2761. The hard layers can be configured toavoid a portion of the carbon fiber mesh that can affect the movement ofthe structure. In FIG. 27B (a), a flexible layer 2711 and a hard layer2761 can be formed, such as printed, on a platform. The flexible layercan be formed at areas needing the flexibility. The hard layer can beformed at areas needing structural support. In FIG. 27A (b), a carbonfiber mesh 2721 can be placed on the flexible layer 2711, and optionallyon the hard layer 2761. The carbon fiber mesh can be secured to theflexible layer or to the hard layer, for example, by taping or gluing tothe platform, to the flexible layer, or to the hard layer.

A second hard layer 2741 can be formed, such as printed, on a portion ofthe carbon fiber mesh 2720 and on the hard layer 2761. The excess carbonfiber mesh can be trimmed, for example, by a laser.

In FIG. 27B (b), a complete structure 2701 of a carbon fiber meshreinforced flexible layer is shown, which can flex for a portion of theflexible layer without the hard layer. Other configurations can be used,such as having another flexible layer on the carbon fiber mesh betweenthe hard layer, so that the carbon fiber mesh is placed between twolayers of flexible material.

In FIG. 27C, a carbon fiber mesh reinforced flexible layer 2702 caninclude a carbon fiber mesh 2722 disposed between two flexible layers2712 and 2772 and a hard layer 2742. The hard layer can be configured toavoid a portion of the carbon fiber mesh that can affect the movement ofthe structure. In FIG. 27C (a), a flexible layer 2712 can be formed,such as printed, on a platform. A carbon fiber mesh 2722 can be placedon the flexible layer 2712. The carbon fiber mesh can be secured to theflexible layer, for example, by taping or gluing to the platform, or tothe flexible layer.

A second flexible layer 2772 and a hard layer 2742 can be formed, suchas printed, on the carbon fiber mesh 2722. The excess carbon fiber meshcan be trimmed, for example, by a laser.

In FIG. 27C (b), a complete structure 2702 of a carbon fiber meshreinforced flexible layer is shown, which can flex for a portion of theflexible layer without the hard layer. Other configurations can be used,such as having another hard layer on the bottom flexible layer.

FIG. 28 illustrates a flow chart for forming carbon fiber meshreinforced flexible layers according to some embodiments. Operation 2800forms a first flexible layer on a substrate. The substrate can beanother layer of a structure.

Operation 2810 forms a first rigid layer on a portion of the firstflexible layer or on the substrate next to the flexible layer. Operation2820 disposes a carbon fiber mesh on the first flexible layer or on therigid layer. Operation 2830 optionally forms a second flexible layer ona portion of the carbon fiber mesh. Operation 2840 optionally forms asecond rigid layer on a portion of the second flexible layer or on aportion of the carbon fiber mesh. Operation 2850 trims the carbon fibermesh using a laser.

FIGS. 29A-29B illustrate processes for forming joints having a carbonfiber mesh reinforced flexible layer according to some embodiments. InFIG. 29A (a), a joint structure 2940 can be formed, including acomponent 2940A that can move with respect to another component 2940B.For example, the component 2940A can rotate 2930 with respect tocomponent 2940B.

In FIG. 29A (b), a flexible layer 2910 can be formed, such as printed,on the joint structure 2940. Bonding elements 2970 can be added, tosecure the flexible layer 2910 to both components 2940A and 2940B of thejoint structure 2940.

In FIG. 29A (c), a carbon fiber mesh 2920 can be placed at least on aportion of the flexible layer 2910. The carbon fiber mesh 2920 can belarge enough to cover the flexible layer, together with a portion of thejoint structure. The carbon fiber mesh can be secured to the flexiblelayer, for example, by taping or gluing to the joint structure, or tothe flexible layer.

In FIG. 29A (d), a second flexible layer 2960 can be formed, such asprinted, on the carbon fiber mesh 2920 on the flexible layer 2910. InFIG. 29A (e), the excess carbon fiber mesh can be trimmed, for example,by a laser to form a complete joint structure 2941. The complete jointstructure 2941 can have the component 2940A rotating around thecomponent 2940B, together with having a carbon fiber mesh reinforcedflexible layer for constraining the two components. This can be appliedto a built bone structure, with the carbon fiber mesh reinforcedflexible layer acting as a tendon or ligament binding the bones togetheror binding the bone with the muscle.

In FIG. 29B (a), a joint structure 2945 can be formed, including acomponent 2945A that can move with respect to another component 2945B.For example, the component 2945A can rotate 2935 with respect tocomponent 2945B.

In FIG. 29B (b), a carbon fiber mesh 2925 can be placed at least on aportion of the joint structure. The carbon fiber mesh can be secured tothe joint structure, for example, by taping or gluing to the jointstructure.

In FIG. 29B (c), a flexible layer 2965 can be formed, such as printed,on the carbon fiber mesh 2925. Bonding elements 2975 can be added, tosecure the flexible layer 2965 to both components 2945A and 2945B of thejoint structure 2945.

In FIG. 29B (d), the excess carbon fiber mesh can be trimmed, forexample, by a laser to form a complete joint structure 2946. Thecomplete joint structure 2946 can have the component 2945A rotatingaround the component 2945B, together with having a carbon fiber meshreinforced flexible layer for constraining the two components.

FIG. 30 illustrates a flow chart for forming carbon fiber meshreinforced flexible layers according to some embodiments. Operation 3000forms a rigid joint structure with movable components. Operation 3010optionally forms a flexible coupling for the rigid joint structure,wherein the flexible coupling is configured for moving the rigid jointstructure. Operation 3020 disposes a carbon fiber mesh on the flexiblecoupling. Operation 3030 optionally forms a flexible layer on a portionof the carbon fiber mesh. Operation 3040 optionally forms a rigid layeron a portion of the second flexible layer or on a portion of the carbonfiber mesh. Operation 3050 trims the carbon fiber mesh using a laser

In some embodiments, the present invention discloses surfaceconditioning a 3D printed object for used in a casting process. A 3Dprinter process can form rough surfaces, for example, due to thelayer-by-layer formation. If the 3D printed object is used in a castingprocess, the rough surfaces can result in cast objects having alsosimilar rough surfaces. By surface conditioning, the object can havedesired surface, such as smooth surfaces, suitable for casting.

In some embodiments, an object can be 3D printed. The surfaces of the 3Dprinted object, e.g., external surfaces and internal surfaces, can beconditioned, such as smoothing or to removing the line features causedby the 3D printing process. The surface conditioning process can beapplied to all surfaces of the 3D printed object, or to selectedsurfaces, such as to surfaces requiring smoothness due to appearance ordue to mating with other components. The conditioned 3D printed objectcan be used as a mold for casting, such as using as a mold in a sandcasting process or in a lost wax casting process.

In some embodiments, the present invention discloses systems and methodsfor surface conditioning a 3D printed object, for example, for used as amold for casting objects. The system can include a 3D printer head forprinting the object, and a surface conditioning head for conditioning asurface of the 3D printed object. The methods can include 3D printing anobject, and then surface conditioning the object. Alternatively, themethods can include 3D printing a portion of the object, surfaceconditioning the printed portion, and then repeating the printing andconditioning processes until the object is complete. The multiplesequences of printing and conditioning can allow surface conditioningareas of the object that can be difficult to reach after the object iscompletely printed.

FIGS. 31A-31B illustrate processes for forming surface conditioning 3Dprinted objects according to some embodiments. In FIG. 31A, an object3130 can be fully printed before subjected to a surface conditioningprocess to form a surface conditioning 3D printed object 3140. In FIG.31A (a), a 3D print head 3110 can be used to print an object 3130, forexample, by printing lines by lines to form a layer, and by printinglayer by layer to form the printed object. Due to the line by line andlayer by layer processes, the surfaces of the printed object 3130, suchas internal surface 3170 and external surface 3150, can be rough, suchas having a line by line texture. In FIG. 31A (b), a surfaceconditioning head 3120 can be used to conditioning the 3D printed object3130 to form a surface conditioning 3D printed object 3140. The surfaceconditioning head 3120 can be a milling head, a sand paper head, aheated head, a flame head or a chemical head, which can be used toconditioning the surfaces, such as smoothing the external rough surface3150 to become a smooth surface 3160, and smoothing the internal roughsurface 3170 to become a smooth surface 3180.

In FIG. 31B, multiple sequences of 3D printing and surface conditioningcan be used, e.g., a sequence of 3D printing and surface conditioningcan be repeated until the object is fully printed and conditioned. Aprocess sequence can include printing a portion of the object, and thensurface conditioning the printed portion, for example, to smooth thesurfaces of the printed portion. The sequence can be repeated until theobject is fully printed and surface conditioned.

In FIG. 31B (a), a 3D print head 3115 can be used to print a firstportion 3132 of an object. Due to the line by line and layer by layerprocesses, the surfaces of the printed portion 3132, such as internalsurface 3172 and external surface 3152, can be rough, such as having aline by line texture. In FIG. 31B (b), a surface conditioning head 3125can be used to conditioning the printed portion 3132 to form a surfaceconditioning printed portion 3142. The surface conditioning head 3125can be a milling head, a sand paper head, a heated head, a flame head ora chemical head, which can be used to conditioning the surfaces, such assmoothing the external rough surface 3152 to become a smooth surface3162, and smoothing the internal rough surface 3172 to become a smoothsurface 3182.

The sequence can be repeated. In FIG. 31B (c), the 3D print head 3115can be used to print a second portion 3134 on top of the first portion3132. The surfaces of the printed portion 3134, such as external surface3154, can be rough. In FIG. 31B (d), the surface conditioning head 3125can be used to conditioning the printed portion 3134 to form a surfaceconditioning printed portion 3144. The surface conditioning head 3125can be used to conditioning the surfaces, such as smoothing the externalrough surface 3154 to become a smooth surface 3164.

The sequence can also be repeated, for example, by printing a thirdportion on the second portion 3134, and the subjecting the printed thirdportion to a surface conditioning process.

By performing multiple sequences of printing and conditioning, innersurfaces of the object, such as as-printed surface 3172, can be surfaceconditioned to form smooth surface 3182. The inner surfaces can bedifficult to conditioned, if the object is fully printed.

FIGS. 32A-32B illustrate flow charts for forming surface conditioningobjects for casting according to some embodiments. In FIG. 32A,operation 3200 forms a system comprising a first head for 3D printingand a second head for surface conditioning. The first head can be afilament extruder head, for printing using polymer filament materials.The first head can be a paste printing head, for printing using pastematerials or solid materials. The first head can be a liquid printinghead, for printing using liquid materials. The second head can be a millhead, for conditioning such as milling surfaces. The second head can bea head having a sand paper coverage, for conditioning such as sandingthe object surfaces. The second head can be a heated head, forconditioning such as smoothing object surfaces by melting. The secondhead can be a flame head, for conditioning such as smoothing surfacesusing open flames. The second head can be a chemical head, forconditioning such as smoothing, surfaces using chemical reactions, suchas acetone vapor. Other head configurations can be used for the secondhead, such as a laser head, or an infrared head.

The two heads can be configured to process a same part, e.g., havingsame process coordinates for printing and conditioning a same object.The two heads can be coupled together, e.g., to a moving mechanism suchas an xyz motion or an articulated robot, so that one head can beoperate and the other head non-operate. The two heads can be separatelycoupled, e.g., one head coupled to a first moving mechanism and theother head coupled to another moving mechanism. Additional heads can beincluded, such as an additional print head, an additional conditioninghead, or other heads such as a laser head, or an infrared head. The twoheads can be coupled to two separate xyz motions, coupled to twoarticulated robots, or to one yz motion and one articulated robot.

In FIG. 32A, operation 3220 forms at least a portion of an object usinga 3D printer head. Operation 3230 conditions a surface of the objectusing a surface conditioning head. Operation 3240 optionally repeatsprinting and surface conditioning.

In some embodiments, the whole object can be printed beforeconditioning. Alternatively, a portion of the object can be printed,then conditioning, before repeating, e.g., repeating printing andconditioning.

In some embodiments, the present invention discloses molding systems forsequentially forming objects for used in a casting process. The moldingsystems can include a 3D print head for forming the objects, and asurface conditioning head for conditioning the surfaces of the objects.The molding systems can include a controller for controlling the twoheads for processing a same objects, e.g., the controller can supply thecoordinates of the objects to the two heads, for example, so that thesurface conditioning head can condition a same point on the objects thatthe print head can print. Additional heads can be included.

FIGS. 33A-33E illustrate configurations of a molding system according tosome embodiments. In FIG. 33A, a molding system can include a print head3310, a surface conditioning head 3320, and an optional controller 3350.The two heads can be coupled to separate linear moving mechanisms, e.g.,motions in xyz coordinates, such as the print head 3310 is coupled tomoving mechanism 3330, and conditioning head 3320 is coupled to movingmechanism 3340. The two heads can be synchronized, e.g., offsetcoordinates of the two heads can be measured. Thus the two heads canprocess a same point, such as by adding or subtracting the offsetcoordinates. For example, the print head can print an object at a firstcoordinate. The controller can add or subtract the offset coordinatesfrom the first coordinate and send the new coordinates to theconditioning head, so that the conditioning head can work on the sameobject at the first coordinate.

Alternatively, each head can have its own set of coordinates, such thatthe zero coordinates of both heads can be pointed to a same point. Thusa same coordinate can mean a same point for the two heads.

In FIG. 33B, a molding system can include a print head 3311, a surfaceconditioning head 3321, and an optional controller 3351. The two headscan be coupled to a same moving mechanisms, such as motions in xyzcoordinates, e.g., both print head 3311 and conditioning head 3321 arecoupled to a xyz moving mechanism 3331. The two heads can be coupled toeach other, and thus can move together. Offset coordinates between thetwo heads can be measured. Thus the two heads can process a same point,such as by adding or subtracting the offset coordinates. For example,the print head can print an object at a first coordinate. The controllercan add or subtract the offset coordinates from the first coordinate andmove the motion mechanism to the new coordinates, thus setting theconditioning head to the same coordinates that the print head justprinted, so that the conditioning head can work on the same object atthe first coordinate. Other moving mechanisms can be used, such as anarticulated robot that is coupled to both heads.

In FIG. 33C, a molding system can include a print head 3312, a surfaceconditioning head 3322, and an optional controller 3352. The two headscan be coupled to separate moving mechanisms, such as the print head3312 is coupled to an xyz linear moving mechanism 3332, and conditioninghead 3322 is coupled to an articulated robot moving mechanism 3342. Thetwo heads can be synchronized, e.g., offset coordinates of the two headscan be measured. Thus the two heads can process a same point, such as byadding or subtracting the offset coordinates. For example, the printhead can print at an origin, e.g., (0,0,0) coordinate. The conditioninghead can access the same (0,0,0) coordinate by using (xoffset, yoffset,zoffset) coordinate, e.g., the (xoffset, yoffset, zoffset) coordinatefor the conditioning head is the same point as the (0,0,0) coordinatefor the print head.

Alternatively, each head can have its own set of coordinates, such thatthe zero coordinates of both heads can be pointed to a same point. Thusthe (0,0,0) coordinate can be the same point for the print head and forthe conditioning head.

In FIG. 33D, a molding system can include a print head 3313, a surfaceconditioning head 3323, and an optional controller 3353. The two headscan be coupled to separate moving mechanisms, such as the print head3313 is coupled to an articulated robot moving mechanism 3333, andconditioning head 3323 is coupled to an xyz linear moving mechanism3343. The two heads can be synchronized so that the two heads canprocess a same point.

In FIG. 33E, a molding system can include a print head 3314, a surfaceconditioning head 3324, and an optional controller 3354. The two headscan be coupled to separate moving mechanisms, such as the print head3314 is coupled to a first articulated robot moving mechanism 3334, andconditioning head 3324 is coupled to a second first articulated robotmoving mechanism 3344. The two heads can be synchronized so that the twoheads can process a same point.

In some embodiments, different print heads can be used to printdifferent materials. Solid materials can be extruded from a heatedextrusion chamber. Paste materials can be extruded from a squeezechamber. Liquid materials can be delivered by a liquid pump such as aperistaltic pump.

FIGS. 34A-34C illustrate different print heads according to someembodiments. In FIG. 34A, a solid material 3420 in the form of a wirecan be provided to a print head 3410. The print head can be heated, forexample, by a heater 3415. The melted or softened material can beextruded out of the print head to be delivered on a support surface,such as a support table or a previously printer surface.

In FIG. 34B, paste material 3430 can be provided to a print head 3412. Aplunger 3450 can be used to extrude the material out of the print head.Optional heater 3415 can be used to heat the paste material. In FIG.34C, liquid material 3442 can be provided to a print head. A peristalticliquid pump 3440 can be used to deliver the liquid material. Forexample, a rotatable mechanism 3446 can be used to squeeze deliveringtube 3444, to move the liquid from a reservoir to the nozzle 3417. Theperistaltic pump can prevent contamination of the printed material, andcan allow the use of different materials for printing without beingcontaminated by the pump.

A peristaltic pump can deliver a liquid material from a reservoir to anozzle. A mechanism can be configured to change the tilted angle of thenozzle, forming a print head having a tilted nozzle. Another mechanismcan be configured to rotate the nozzle. For example, the peristalticpump can be rotated through a rotatable seal. In some embodiments, asolidify mechanism, such as a cooler, can be coupled to the print headto solidify the liquid material. The liquid material can be in a pasteform, and when delivered on a cold substrate, can be further solidifyinto solid form.

A peristaltic pump can be used to print a liquid object, which can besolidified on a cold platform. A print head can include a peristalticpump to a nozzle. An optional heater can be used to regulate thetemperature of the liquid. The temperature of the environment of theprint head can be regulated to allowing printing liquid materials. Forexample, a cooling system can be coupled to a support platform 5020 tokeep the delivered materials at a solid state. Further, the print headcan be placed in a controlled environment, which can regulate thetemperature of the printed materials.

In some embodiments, a liquid printhead, e.g., a printhead having aliquid pump (such as a peristaltic pump) for delivering a liquid, can beused in conjunction with a non-liquid printhead, e.g., a printhead nonconfigured to deliver a liquid, such as a solid printhead (e.g., aprinter hear configured for delivering a soften or melted solid materialthat can be solidified after leaving the printhead) or a paste printhead(e.g., a printer hear configured for delivering a paste material thatcan be solidified after leaving the printhead). Two or more printheadscan be used in a 3D printing system with at least one printhead being aliquid printhead.

In some embodiments, the liquid printhead can be used to separate thesolid layers. For example, two objects can be printed together. The twoobjects can be prevented from adhering to each other by a layer ofliquid in between, such as a layer of lubricant materials, such as anoil layer delivered by a liquid printhead configured to deliver oil. Alayer of the first object can be printed, followed by a layer of liquid,such as oil. The liquid layer can printed on a portion of the firstlayer or on the whole first layer. A layer of the second object can beprinted on the liquid layer. The process can be repeated until the twoobjects are printed.

In some embodiments, the liquid printhead can be used to improve theadhesion of two layers. For example, two layers can be printed with anaddition liquid adhesion layer in between to improve the adhesion ofthese two layers. In some embodiments, a paste printhead can beconfigured to deliver a layer of lubricant or a layer of adhesion.

Two printheads can be installed in a 3D printing system. In someembodiments, at least one of the printheads is a liquid printhead.

A 3D printing system can include a solid printhead and a liquidprinthead. In the solid printhead, a solid material in the form of awire can be provided to a print head. The print head can be heated, forexample, by a heater. The melted or softened material can be extrudedout of the print head to be delivered on a support surface, such as asupport table or a previously printer surface. In the liquid printhead,a liquid material can be provided to a nozzle head. A peristaltic liquidpump can be used to deliver the liquid material. Other liquid pump canalso be used. The operation of a peristaltic pump is shown, in which arotatable mechanism can be used to squeeze delivering tube, to move theliquid from a reservoir to the nozzle head.

A 3D printing system can include a paste printhead and a liquidprinthead. In the solid printhead, paste material can be provided to aprint head. A plunger can be used to extrude the material out of theprint head. Optional heater can be used to heat the paste material. Inthe liquid printhead, a liquid material can be provided to a nozzlehead. A peristaltic pump is shown, but other liquid pump can be used.Other configurations for a printing system can be used, such as a solidprinthead and a paste printhead.

A 3D printing system can include multiple printheads. In someembodiments, at least one of the printheads is a liquid printhead, whichis configured to deliver a liquid layer, such as a lubricant layer or anon-stick layer. In some embodiments, the liquid printhead can beconfigured to deliver an adhesion layer, such as a glue layer, to bondto adjacent layers. For example, multiple solid or paste printheads canbe used with one or more liquid printheads.

In some embodiments, a paste printhead can be used in place of theliquid printhead to deliver a separation layer (such as a lubricantlayer), or an adhesion layer (such as a glue layer). In someembodiments, at least one of the printheads is a paste printhead, whichis configured to deliver a paste layer, such as a lubricant layer, anon-stick layer, or an adhesion layer. For example, multiple solid orpaste printheads can be used with one or more paste printheads.

In some embodiments, a paste printhead can be used in place of theliquid printhead to deliver a separation layer (such as a lubricantlayer), or an adhesion layer (such as a glue layer).

In some embodiments, a mist can be delivered, instead of a liquid orpaste layer. A printhead can be configured to deliver a fine mist over afirst layer before printing a second layer, to either prevent stickingor to increase adhesion.

In some embodiments, a brush of layer can be delivered, instead of aliquid or paste layer. A printhead can be configured to brush a layerover a first layer before printing a second layer, to either preventsticking or to increase adhesion.

In some embodiments, different conditioning heads can be used tocondition the surfaces of the printed objects. The conditioning head canuse physical conditioning, such as cutting, milling, or sanding. Theconditioning head can use thermal conditioning, such as heating byconduction, e.g., heating by contacting the surfaces of the printedobjects, or heating by radiation, e.g., heating by infrared radiation onthe object surfaces, or heating by open flame. The conditioning head canuse chemical conditioning, such as exposing the object surfaces to achemical, such as acetone vapor can smooth the surfaces of ABS objects.

FIGS. 35A-35I illustrate different conditioning heads according to someembodiments. FIG. 35A shows a ball cutter tool 3520, e.g., a millingcutter having a ball shape, which includes cutter tools for performingmilling operations, e.g., removing materials by the movement within themachine (such as a ball nose mill) or directly from the cutter shape.The ball cutter tool 3520 can include a shaft 3540, together with a ballshape cutter 3530 at one end of the shaft. Other cutters with differentshapes, such as oval or rounded cylinder, can be used.

FIG. 35B shows a cutter tool 3521, e.g., a milling cutter having acylindrical shape. The cutter tool 3521 can include a shaft 3541,together with a cylindrical shape cutter 3531 at one end of the shaft.Other cutters with different shapes, such as taper cylinder, can beused.

FIG. 35C shows a cutter tool 3522, e.g., a milling cutter having a ballshape. The cutter tool 3522 can include a shaft 3542, forming an anglewith a ball shape cutter 3532. Other cutters with different shapes andangles, such as oval, rounded cylinder, taper cylinder, or acute orright angles, can be used. The angles can be adjustable.

Other cutter tools can be used, such as end mill tools, including flatbottomed cutters, rounded cutter, e.g., ball nosed cutters, and radiusedcutters, e.g., bull nose or torus, side and face cutter tools, face millcutter tools, and any other types. The cutter tools can be used tosmooth a surface of the printed objects, for example, by cutting awaythe roughness of the surface.

FIG. 35D shows a configuration for a heated conditioning head 3523. Theheated conditioning head 3523 can include a heater 3553 for heating aheatable element 3533, which can include metal or alloy materials. Theheatable elements can run across a surface, and the irregular surfaceelements can be smoothened, e.g., by melting the protruded portions andfilling the recessed portions. The heatable elements 3533 can have aheight h larger than a width w. The larger height can be used forrunning along a vertical surface, which can smooth the vertical surface.Similarly, the width can be used for running along a horizontal surface.The larger height can allow the conditioning head to process a verticalsurface faster than a horizontal surface. Tilted surfaces can beconditioned, for example, by using a corner of the heatable element3533.

FIG. 35E shows another configuration for a heated conditioning head3524. The heated conditioning head 3524 can include a heater 3554 forheating a heatable element 3534. The heatable elements 3534 can have aheight h smaller than a width w. The larger width can allow theconditioning head to process a horizontal surface faster than a verticalsurface. Tilted surfaces can be conditioned, for example, by using acorner of the heatable element 3534.

FIG. 35F shows another configuration for a heated conditioning head3525. The heated conditioning head 3525 can include a heater 3555 forheating a heatable element 3535. The heated conditioning head 3525 canhave a tilted shaft 3545 forming an angle θ with a vertical shaft. Thetilted shaft can allow conditioning tilted surfaces.

Other heated conditioning heads can be used, such as heated conditioningheads having rotatable shafts, thus allowing a fast conditioning oftilted surfaces. Further, the heated conditioning heads can have theheatable elements rotatable, e.g., around the shaft of the heatedconditioning heads.

FIG. 35G shows a conditioning head 3526 for sanding, for example, byhaving a sand paper 3556 covering a support element 3536. Theconditioning head 3526 can rotate around a shaft 3546, and can smoothsurfaces of printed objects. Other configurations can be used, such astilted support elements, or rotatable support elements, e.g., forforming an angle with respect to the shaft 3546.

FIG. 35H shows a conditioning head 3527 for flame conditioning asurface, for example, by providing an open flame 3537 to the surface forsmoothing the irregularities or roughness of the surface. Theconditioning head 3527 can rotate around a shaft 3547, and can smoothsurfaces of printed objects. Other configurations can be used, such astilted support elements, or rotatable support elements, e.g., forforming an angle with respect to the shaft 3547.

FIG. 35I shows a conditioning head 3528 for chemical conditioning asurface, for example, by providing a chemical vapor or liquid 3538 tothe surface for smoothing the irregularities or roughness of thesurface. The conditioning head 3528 can rotate around a shaft 3548, andcan smooth surfaces of printed objects. Other configurations can beused, such as tilted support elements, or rotatable support elements,e.g., for forming an angle with respect to the shaft 3548.

FIGS. 36A-36B illustrate flow charts for casting objects using surfaceconditioning printed objects according to some embodiments. In FIG. 36A,an object can be formed by printing and surface conditioning, includingusing multiple sequences of printing and surface conditioning. Theobject can be used as a mold for casting, such as a sand castingprocess, or a lost wax casting process. The object can be a positiveimage of the cast object, which can be used to cast an object directly.The object can be a negative image of the cast object, which can be usedto cast a mold. The mold is then used for casting the object.

Operation 3600 forms an object using a 3D printing process and a surfaceconditioning process. Operation 3610 forms a cast object using theobject as a mold.

In FIG. 36B, operation 3630 forms an object or a portion of an objectusing a 3D printer assembly. Operation 3640 conditions a surface of theobject or the portion of the object using a surface conditioningassembly. The process can be repeated until the object is completed.Operation 3650 casts a second object using the surface conditioningobject.

What is claimed is:
 1. A print head comprising two shafts, wherein eachshaft is hobbed at a portion of the shaft, wherein the hobbed portionsof the shafts are configured to contact a filament, wherein the shaftsare configured to rotate in opposite directions for driving thefilament; a heated chamber, wherein the heated chamber is configured toreceive the filament driven by the two shafts, wherein the heatedchamber is configured to deliver a molten material from the filament. 2.A print head as in claim 1 wherein one shaft is coupled to a motor,wherein the two shafts are coupled together through a couplingmechanism.
 3. A print head as in claim 1 wherein each shaft is coupledto a motor.
 4. A print head as in claim 1 further comprising an assemblyconfigured to adjust a distance between the two shafts.
 5. A print headcomprising a conduit, wherein the conduit comprises a channel forguiding a filament; two motors, wherein each motor comprises a shaft,wherein the conduit comprises two cut portions for accepting the twoshafts, wherein each of the two cut portions expose a portion of thechannel, wherein the two shafts are configured to rotate in oppositedirections for driving the filament along the channel; a heated chamber,wherein the heated chamber is coupled to the conduit for receiving thefilament driven by the two shafts, wherein the heated chamber isconfigured to deliver a molten material from the filament.
 6. A printhead as in claim 5 wherein the two shafts are disposed in parallel witheach other and perpendicular to the conduit, wherein the two shafts areconfigured to be in opposite sides of the filament and contacting thefilament.
 7. A print head as in claim 5 wherein at least one shaft ofthe two shafts contacts the filament through the exposed portion,wherein the at least one shaft is hobbed at least in an area that the atleast one shaft contacts the filament.
 8. A print head as in claim 5wherein the two shafts contacts the filament through the exposedportions, wherein both shafts of the two shafts are hobbed at areascontacting the filament.
 9. A print head as in claim 5 wherein a gear iscoupled to at least one shaft of the two shaft, wherein the gearcontacts the filament through the exposed portion.
 10. A print head asin claim 5 wherein the two motors are disposed in opposite directionswith respect to the conduit.
 11. A print head as in claim 5 furthercomprising an assembly coupled to one shaft of the two shafts forpushing the one shaft to the other shaft of the two shafts.
 12. A printhead as in claim 5 further comprising a spring assembly coupled to oneshaft of the two shafts for adjusting a distance between the two shafts.13. A print head as in claim 5 further comprising an assembly coupled toone motor of the two motors for adjusting a distance between the twoshafts.
 14. A print head as in claim 5 wherein each motor is coupled toa motor mount, wherein the print head further comprises an assemblycoupled to one motor mount of the two motor mounts for adjusting adistance between the two shafts.
 15. A print head as in claim 5 whereineach motor is coupled to a motor mount, wherein the two motor mounts arecoupled to each other so that one motor mount of the two motor mounts isconfigured to move with respect to the other motor mount, wherein theprint head further comprises an assembly coupled to one motor mount ofthe two motor mounts for adjusting a distance between the two shafts.16. A print head as in claim 5 wherein the print head is configured tobe coupled to a 3D printer.
 17. A print head as in claim 5 furthercomprising an acoustic sensor for detecting a condition of the twomotors.
 18. A print head as in claim 5 further comprising an acousticsensor for detecting a contact of the print head with an object.
 19. Aprint head as in claim 5 further comprising an acoustic sensor forleveling a platform.
 20. A method comprising activating two motors torotate in opposite direction, wherein each motor comprises a shaft,wherein the two shafts are configured to drive a filament along achannel of a conduit to a heated chamber for delivering a moltenmaterial; moving the two motors to print an object with the moltenmaterial.